Home Horticulture:
Answers to Frequently Asked Questions

How and when do I prune my shrubs?

Time of pruning varies with plant species. Spring-flowering shrubs (forsythia, deutzia, azalea, spirea, etc.) are normally pruned after flowering. Pruning spring-flowering shrubs during the dormant season will remove flower buds because they bloom on the previous season's growth. Summer-flowering shrubs (abelia, butterfly bush, crape myrtle, etc.) generally are pruned during the dormant winter season. For non-flowering shrubs, the best time for pruning is during the dormant winter season before growth begins in the spring. Light, corrective pruning can be done at any time of the year. Avoid heavy pruning during the late summer and fall because regrowth may occur and make the plants more susceptible to cold injury.

When pruning, first removed any dead, diseased, or damaged wood. Then carefully select and remove branches while maintaining the natural shape of the plant. A good pruning job should not be conspicuous! There are five basic techniques for pruning shrubs:

1) pinching - removing the tip of a succulent, green shoot before it becomes woody and firm. Done to reduce length and encourage branching.

2) heading back - cutting a branch back to a healthy bud or branch to stimulate growth and increase bushiness.

3) thinning - removing a branch at its point of origin (ground, parent stem, side branch, etc.) to create a more open plant without stimulating new growth.

4) renewal pruning (rejuvenation) - removing the oldest branches by pruning them near the ground, leaving the younger, more vigorous branches (which may also be pruned). Abelia, deutzia, forsythia, spirea, and weigela are pruned using this method.

5) shearing - removing the tips of most branches with shearing or hedge clippers. Shearing should be used sparingly as it destroys the natural shape of the plant and inhibits light penetration, eventually causing dieback in the interior of the shrub.

For more information, check out these on-line publications:

Basic Principles of Pruning Woody Plants
Pruning Broadleaf Evergreen Shrubs
Pruning Narrowleaf Evergreens (Conifers)
Shrub Pruning Calendar


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How and when do I prune my trees?

Proper pruning can lengthen a tree's life, increase its value, and minimize liability problems. Incorrect pruning can cause pest and decay problems, increased liability (from deadwood, splitting, etc.), and greatly reduce the tree's life span.

Late dormant season pruning of trees is usually recommended, although light, corrective pruning (removal of any dead, diseased, or damaged wood) can be done at any time of the year. Examine the branch growth pattern along the main trunk. Ideally branch growth should alternate along the trunk. You should not have two or more branches attached at the same location along the trunk (except for trees that produce branches in whorls, such as pines, cedars, hemlocks, spruces, and firs). Remove branches with a narrow crotch angle because they are weakly attached to the tree. Prune forks to a single limb. Trees should never be topped (see the question on topping).

When making a pruning cut, examine the branch to locate the branch-bark ridge and the branch collar. The branch-bark ridge is where the growing, expanding branch and the expanding trunk push up bark between them into a raised ridge at the base of the branch. There is a slight swelling on the underside of the branch as it enters the trunk. The area around and between the branch-bark ridge and the bottom swelling is called the branch collar. When pruning, you want to cut the branch but not the branch collar. Cut the base of the branch at the edge of the collar. Do not flush cut or leave a long stub. Do not use wound paints because they disrupt the tree's ability to seal off its wound site.

For more information, check out these on-line publications:

Basic Principles of Pruning Woody Plants
Pruning Shade Trees
Pruning Trees, Flushcuts, and Wound Dressings
Landscape Tree Care 101


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Should I "top" my trees?

Topping violates proper pruning techniques and is one of the worst things you can do to your tree. Topping is the indiscriminate cutting back of tree branches to stubs. Most people top their trees to reduce its size. Topping stresses trees, causes decay, creates hazards, and ruins the natural beauty of the tree. Trees that have been topped are more prone to storm damage as well as insect and disease problems. Follow correct pruning practices to reduce a tree's height or spread (see question on pruning trees). You may want to hire a professional arborist to recommend the best strategy. Sometimes the best solution is to remove the tree and replace it with a species that is more appropriate for the site.

For more information, check out these on-line publications:

Why Topping Hurts Trees
Basic Principles of Pruning Woody Plants


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What is causing my shade tree to die back?

Shade tree decline can be caused by a number of factors. One of the most common errors I see occurs at planting time. Many people plant trees too deep, which can suffocate the roots. Dig planting holes 2-3 times as wide as the root ball and plant the tree the same depth as the root ball. Many people plant very large and expensive trees to get the effect of an "instant landscape". However, large trees may experience several years of transplant shock because they have so much more canopy than their roots can support. In the long run, it may be better to start with a smaller tree and provide good maintenance.

One of the major causes of tree decline is planting a tree in a location to which it is not suited: a shade-loving tree in full sun, a large tree in a confined location, a tree intolerant of air pollution in an urban landscape, or a tree that prefers well-drained soil in a swampy area. Choose a tree that is well-adapted to local conditions.

Other factors which place trees under stress and lead to decline include drought, pest epidemics, and alterations of natural dainage. Improper pesticide applications can damage trees. Construction activities that compact the soil, change the grade, and damage or suffocate roots are a major cause of tree decline. Often symptoms do not appear for several years after the trenching or construction occured. It is important to protect the root zone of the tree all the way to the dripline to minimize damage from construction or digging activities.

You must try and determine the stress that is causing decline. Has there been any recent digging or other activity that damaged the roots, or improper planting? Is the tree well- adapted to the site? Drought from years past causes alot of stress., with symptoms often appearing years later. Examine the leaves for signs of disease or insect damage (mildew, spots, holes, etc.). If you see evidence of a pest you may want to call the Extension office for help with diagnosis.

To prevent tree decline, first choose the appropriate tree for the site. Follow correct guidelines for planting, fertilization, pruning, and watering. Avoid wounding the tree with lawn mowers, equipment, nails, etc. Be careful when applying pesticides around the tree, especially herbicides which may drift onto the tree or enter the soil and cause damage. Do not top trees (see question on topping). Avoid compacting the soil around the root zone.

For more information, check out these on-line publications:

Tree Decline: Causes, Symptoms, and Prevention
Site Disturbance and Tree Decline


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What are these funny spots on the leaves of my maple tree?

Maple leaves can often be found in the summer with spots on them that resemble eyes or targets. These are eyespot galls caused by a midge, or tiny fly. The midge lays it eggs on the underside of the leaf and as the larvae hatches and develops it releases a growth regulating hormone that produces the brightly colored rings around the gall. The midge larvae completes its development in about 10 days and drops to the ground to pupate. The gall is considered a cosmetic problem and does not have a serious effect on the tree. No control is available.

For more information, check out this on-line publication:

Common Maple Galls


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What is causing small tree branches to fall off? It looks like they were sawed off.

A beetle called the twig girdler is likely responsible for this damage. Damage is usually noticed in late summer when twigs and branches fall to the ground, cut as neatly as if by a knife. The adult female twig girdler cuts a small incision through a twig and then inserts her egg into a gnawed hole towards the tip of the twig above this incision. The larva hatches and feeds inside the twig, eventually severing the branch. Winds often cause the branch to fall to the ground. The larva overwinters and pupates inside the twig (even if it has fallen to the ground) and the adult emerges in late summer.

Since the twig girdler larva is inside the twig when it falls from the tree, the best control is to gather and destroy fallen girdled twigs.

For more information, check out this on-line publication:

Twig Girdler


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My mimosa tree is wilting and dying. What can I do?

Mimosa trees in the southeast are susceptible to a serious disease called mimosa vascular wilt. Mimosa wilt, or Fusarium wilt, is caused by a soil-born fungus that invades trees through the root system. Usually the leaves turn yellow and wilt, or they may drop before wilting. Branches die one by one. Severely infected trees may ooze a frothy liquid from cracks in the trunk. There are no effective control measures for mimosa wilt. Since most trees die within a year of first displaying wilt symptoms, the best strategy is to remove the tree and replace it with a species that is resistant to Fusarium wilt.

For more information, check out this on-line publication:

Mimosa Vascular Wilt


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What is this white film on the leaves of my shrubs and trees?

The white film you are seeing is most likely a fungal disease called powdery mildew. Powdery mildew attacks a wide variety of ornamental plants in North Carolina. The disease usually occurs during spring, fall, and winter months during cool weather with high relative humidity. Young plants with succulent new growth are particularly susceptible to powdery mildew problems. The fungus can infect leaves and flowers. Plants such as crape myrtle, roses, zinnias, and euonymous are particularly susceptible. If the problem is severe, prune out severely infected portions and then apply a fungicide such as sulfur, copper, Immunox, or Funginex. Improve air circulation and rake up and destroy leaves in the fall.

For more information, check out this on-line publication:

Powdery Mildew of Ornamentals and Shade Trees


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What is this black film on the leaves of my shrubs and trees?

The black film you are seeing may be sooty mold, a fungus that grows on the honeydew secreted by plant-sucking insect pests such as aphids, mealybugs, or scales that feed on the sap inside leaves. The water and sugars ingested by the insects are excreted as honeydew, which adheres to leaves and also drops to objects below. Sooty molds are not plant parasitic, but they can be unsightly and even decrease the vigor of a plant by blocking the sunlight required for photosynthesis. Since the presence of sooty mold indicates a pest problem, the first step in control is to identify and suppress the insects. Horticultural oils provide good control of such sucking insect pests and also help to loosen the sooty mold.

For more information, check out these on-line publications:

Sooty Molds
Horticultural Oils as Insecticides


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What is causing the leaves of my azaleas to look stippled and bleached-out?

Azalea lace bugs are found most often on the undersides of leaves. The adults are about 1/8 inch long with lace-like wings. They feed on the leaves, causing a blotched or stippled appearance on the upper leaf surface. Dark spots of excrement can be found on the undersides of the leaves. Infested leaves turn yellow and drop. Orthene and Malathion can be used to control severe infestations of lace bugs. Make the first application as soon as the young nymphs appear in the spring. A second application may be needed 7-10 days later. Thorough coverage of the leaves is essential, including the undersides.

For more information, check out this on-line publication:

Lace Bugs


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Why are my azaleas dying?

Azaleas are susceptible to a number of problems in the landscape. Phytophthora root rot is a fungal disease that can severely inhibit plant growth and decrease life span. This disease is favored by high soil moisture and warm temperatures. Planting azaleas too deep, overwatering, or excessive rainfall can contribute to root rot. No effective controls are available for established plantings in home landscapes. Prevention is the best strategy. Buy disease-free plants, plant in well-drained areas, avoid planting too deep, and provide optimal growing conditions. Replace diseased plants with resistant species.

Azaleas are also susceptible to nematodes, tiny worms that live in the soil and feed on plant roots. Leaves may turn yellow, plants may be stunted and gradually die. No effective controls are available for established plantings in home landscapes. The best thing you can do is to provide optimal growing conditions (mulch, partial shade, and appropriate amounts of water and fertilizer).

Phomopsis twig blight is another possibility. This is a fungal disease that causes wilting or death of branches amd produces a reddish discoloration under the bark. Prune out and destroy diseased branches several inches below infected area.

If you suspect disease or nematodes, you may want to submit a sample to the Cooperative Extension office for diagnosis. To submit a diseased specimen, bring a quart of soil along with some roots from the sick plant, as well as a sample of the infected branch and foliage. Try to bring a sample that is showing symptoms but is not totally dead. Keep the soil and foliage samples in separate bags to prevent contamination. It is best to submit samples no later than Wednesday, so that if they need to be sent to the NCSU diagnostic lab, they will arrive by the end of the week (a sample that sits over the weekend often deteriorates so badly it makes diagnosis difficult).

Improper fertilization can also damage azaleas. Azaleas have shallow roots so they are susceptible to fertilizer injury. It is better to apply small amounts of fertilizer in March, May, and July than to apply all the fertilizer at once.

Voles can also damage azaleas and produce above-ground symptoms. Check for evidence of vole tunnels under mulch. See the publication on voles for control strategies. Keep mulch pulled back several inches away from plant stems to reduce protective cover for the voles.

For more information, check out these on-line publications:

Azalea (Rhododendron sp.) Diseases
Controlling Insects and Diseases on Azaleas and Rhododendrons
Azalea Culture for North Carolina
Azalea Culture for Georgia Gardeners


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How do you control Japanese beetles on ornamentals?

Because Japanese beetles produce large numbers of grubs, the larval stage of this insect actually causes more damage than the flying adults. The C-shaped white grubs feed on roots and organic matter in the soil. The tunneling of the foraging grubs creates a spongy feel to the soil and turf. Where infestation is heavy, the damaged turf can be rolled back liked carpet, revealing the feeding grubs underneath. Grubs burrow deep into the ground to overwinter, and return to the soil surface in the spring as the soil temperature warms. Adults emerge in late June or July and begin feeding immediately. The early arrivals release a congregation pheromone (odor) which attracts later-emerging adults to gather en masse and feed on the selected plant. The females will feed, mate, and lay eggs throughout the summer.

Control efforts can be targeted at both adults and grubs. Plums, golden sycamores, witchazels, roses, and many varieties of grapes are particularly attractive to beetles, and you may consider replacing some of them with non-attractive plants if you are fighting a losing battle against this pest. The list of non-attractive plants is lengthy and includes hollies, verbena, hydrangea, euonymus, coneflower, gardenia, lantana, larkspur, pyracantha, and many others.

If you are experiencing problems on just a few plants, the adults can be hand-picked into a jar of soapy water. If your problem is widespread, then pesticides may be warranted. Liquid Sevin, malathion, and Orthene (on ornamentals) have proven effective. The efficacy of traps is debatable, as they often attract more beetles than they catch. When you peer into the trap and see dozens of beetles you may think the trap is effective, but you are not seeing the beetles that were attracted and not trapped. If you do decide to use a trap, be sure and place it far away from susceptible plants because the dead beetles release ammonia which repels beetles. The bait is attractive over fairly long distances, while the ammonia is repellant to beetles in the vicinity of the trap, so if you don't empty the trap regularly you will attract more beetles than you trap.

Grub control is extremely important for effective beetle management. Soil insecticides such as diazinon can be applied in late summer or early fall when the grubs are feeding near the soil surface. Water the lawn thoroughly after application to move the insecticide down into the soil.

A biological control agent called milky spore disease can be applied for long-term grub control. Milky spore is a naturally occurring bacterium that is fatal to Japanese beetle grubs but harmless to all other organisms. It is applied as a dust or powder and one application can last in the soil for over 10 years. It may take 2-3 years for the spore count to build up enough for maximum results. The larvae become infected with the disease and release billions of disease spores into the soil when they die. This is why milky spore will not spread unless grubs are present in the soil. The more numerous the grubs, the faster the beneficial disease is established in your lawn. Once the grubs are destroyed, milky spore lies viable and dormant in the soil, awaiting more grubs.

For more information, check out this on-line publication:

Japanese Beetles


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What is this strange moss-like growth on my azalea branches?

The growth you are seeing on the branches is probably lichen, a combination of green algae and fungi that is found growing in moist, shady areas. They range in color from brown to green and appear crusty or leaf-like. Lichens do not hurt the plant but indicate that the plant is under stress.

For more information, check out this on-line publication:

Lichens on Trees and Shrubs


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Why are my junipers turning brown?

You will probably need to submit a sample for diagnosis to your local Extension office because there are several possibilities. Junipers are susceptible to a number of diseases such as twig blight and Phytopthora root rot that can lead to decline. Nematodes, winter injury and drought stress can also cause branches to die back. Spider mites can cause needles to look gray or dirty.

Instructions for submitting a diseased specimen: Bring a quart of soil along with some roots from the sick plant, as well as a sample of the infected branch and foliage. Try to bring a sample that is showing symptoms but is not totally dead. Keep the soil and foliage samples in separate bags to prevent contamination. It is best to submit samples no later than Wednesday, so that if they need to be sent to the NCSU diagnostic lab, they will arrive by the end of the week (a sample that sits over the weekend often deteriorates so badly it makes diagnosis difficult).

For more information, check out these on-line publications:

Southern Red Mite and Spruce Spider Mite
Juniper Diseases and Their Control in the Landscape


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What are these insects on my gardenias?

A number of insects are considered gardenia pests, but the most common pests are whiteflies, mealybugs, and scales. Whiteflies are tiny (1/12" long) winged insects found mainly on the undersides of leaves. When disturbed, they fly above the foliage in a small cloud. Mealybugs are soft-bodied insects that are closely related to scales. They cover themselves with white or gray waxy threads, and heavy infestations of mealybugs make the plant look like it is covered in cotton. Scale insects produce a protective armor and appear as tiny bumps along the leaves and stem. All of these pests are sucking insects, so infested plants become sticky with honeydew and dark with sooty molds. Horticultural oils provide good control.

For more information, check out these on-line publications:

Whitefly
Mealybugs
Hemispherical Scale
Sooty Molds
Horticultural Oils as Insecticides


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Why are the edges of my rose petals turning brown?

A tiny, slender, winged insect called the Western flower thrips is the most likely culprit. Thrips feed on the petals, causing pale spots and brown patches and streaks. To check for thrips, remove an infested bloom and shake it over a piece of white paper. The tiny yellow or brown thrips should fall out and be visible against the white background. It is difficult to control thrips with pesticides because they are so mobile and continuously migrate to roses from neighboring plants. Infested buds and blooms should be removed and destroyed. Orthene can be used to provide some control.

For more information, check out this on-line publication:

Western Flower Thrips


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What are these black spots on my rose leaves?

Black spot, a fungal disease, is the most serious disease of roses in North Carolina. Black spot cannot be adequately controlled without a regular fungicide spray program. Daconil alternating with either Funginex or Immunox can be used. It is necessary to have a uniform spray on both sides of the leaves. Spraying must begin as new growth starts in the spring and continued at 7-10 day intervals throughout the growing season. Remove infected leaves as they appear and rake up and discard fallen leaves during the fall. Remove old mulch and replace before new growth begins in the spring. Improve air circulation and relocate plants to full sun. Consider some of the disease- resistant antique roses if you do not wish to spray pesticides regularly.

For more information, check out this on-line publication:

Rose Diseases and their Control in the Home Garden


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How and when do I fertilize and prune my azaleas?

Azaleas do best with a moderate but even level of fertilizer in the soil. Your best strategy is to conduct a soil test to determine specific fertilizer needs. In the absence of a soil test, use an 8-8-8 or a 10-10-10 fertilizer. Split applications ahould be made in March, May, and July. Small plants (<12" tall) should receive 1 ieaspoon per application. Larger plants should receive approximately 1 level tablespoon per foot of height per application. For large bed areas, 2-3 pints per 100 square feet can be broadcast. Over-fertilization can cause severe damage. The only way to truly determine fertilizer requirements is to conduct a soil test. Do not lime azaleas unless recommended by a soil test. Azaleas are pruned immediately after flowering.

For more information, check out these on-line publications:

Azalea Culture for North Carolina
Azalea Culture for Georgia Gardeners


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Can I take cuttings from my shrubs? How and when do I do this?

The best time to take cuttings depends on the type of plant. It is best to take cuttings in the early morning. Keep cuttings cool and moist until they are stuck. Cut a 4-6" long section of the stem, then remove the leaves from the lower 1/3 to 1/2 of the cutting. Treat the cutting with a root-promoting compound and stick into an appropriate rooting medium that is sterile, low in fertility, and well-drained. Materials commonly used for rooting mediums include coarse sand, a mixture of one part peat and one part perlite, or one part peat and one part sand. Water the medium before sticking the cutting. Insert the cutting 1/3 to 1/2 its length into the medium. Cover the cuttings with plastic and place in indirect light. Keep the medium moist until the cutting has rooted. Consult the publication listed below for optimal times for rooting stem cuttings as well as detailed procedures.

For more information, check out these on-line publications:

Plant Propagation by Stem Cuttings
Other Propagation Fact Sheets from NCSU


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How come my flowering shrub is not blooming?

There are several reasons plants fail to bloom:

1) over-fertilization with nitrogen: nitrogen stimulates leaf production and reduces flower production.

2) excess shade: can stunt plants and delay or prevent flower set.

3) improper pruning: some plants flower on the previous season's growth, so pruning in early spring removes the flower buds. Prune spring-flowering plants after they finish flowering. Drastic pruning can also reduce flowering.

4) cold injury or drought stress: when practical, protect plants during severe cold spells. Water during drought periods and mulch.

5) incorrect fertility: conduct a soil test to determine if there are nutrient problems.

6) juvenile plant: some plants will not flower until they reach a certain age, or until they become established after transplanting.


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What is this spider-like webbing on the leaves of my shrubs?

Fine webbing in the foliage of plants indicates the presence of spider mites. The mites are very tiny and usually found feeding on the undersides of leaves. They extract sap from the leaves and a heavy infestation can cause a plant to become yellowed, bronzed, or even killed completely. Thorough application of a pesticide to the undersides of the leaves is necessary for good control. Horticultural oils and insecticidal soaps provide cood control of spider mites.

For more information, check out this on-line publication:

Two-Spotted Spider Mites


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How do you control bagworms on Leyland cypress?

Bagworms can be removed with scissors if they are not too numerous. Insecticides such as Orthene, Dipel, and malathion can be applied in June or early July when the bagworms are small and vulnerable. Several species of native parasitic wasps also help control bagworm populations.

For more information, check out this on-line publication:

Bagworms


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When and how do I fertilize my trees and shrubs?

Trees and shrubs in the landscape do not necessarily need to be fertilized annually. Fertilization rates should be based on soil test results, current and desired growth rate, plant age, type, location, or by using general guidelines. Normally 2-4 lbs. of a complete fertilizer per 1,000 square feet is recommended for optimum growth. If you want more new growth, use the higher end of this range. For small trees and shrubs, use 1/2 to 1 cup of 10-10-10 fertilizer. The amount of fertilizer should not exceed 1 level tablespoon per foot of height for fertilizers containing 10 or more percent nitrogen. For large trees, measure the trunk diameter 4 feet from the ground and apply 0.1 lb. of actual nitrogen (0.1 lb. of actual nitrogen equals 1 lb. of 10-10-10) for each inch of trunk diameter. Or simply broadcast 0.1 lb. of actual nitrogen per 100 square feet. Remember, your best bet is to conduct a soil test and follow the recommendations.

Fertilize trees and shrubs in the spring or fall. Spring fertilizer application should be made before new growth starts. Fall fertilization should be made about one month after the first killing frost. Avoid fertilizing in late summer (mid-August) because it can stimulate new growth and increase the chance of cold injury.

For more information, check out these on-line publications:

Fertilizing Deciduous Shade Trees in the Landscape
NCSU Teletip: Fertilizing Trees and Shrubs


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How do I get rid of caterpillar nests in trees?

Fall webworms typically build their nests at the tips of tree branches in the fall. Eastern tent caterpillar nests are built in the crotch of branches in the spring. These nests are usually not numerous enough to cause serious damage to ornamental trees, but large numbers of nests can cause severe defoliation. The webbing provides protective cover for the feeding caterpillars so anything you can to to disrupt the nest will make the caterpillars more vulnerable to predators. A water hose or rake can be used to tear open the nest. Prune out and destroy fall webworm nests from the tips of branches. A Bt product such as Dipel can be sprayed on the nest and surrounding foliage when the caterpillars are small. Orthene can also be used. For best results, spray in late morning when the caterpillars congregate on the outside of the tent surface to warm in the sun. The egg masses are easy to spot once the leaves have fallen in the winter. Remove these egg masses and destroy.

For more information, check out these on-line publications:

Eastern and Forest Tent Caterpillars and Their Control
Fall Webworm Management


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What is wrong with my red tip photinias?

Red tip photinias are very susceptible to Entomosporium leaf spot , a fungal disease that can cause severe damage. Disease spores are spread by wind or splashing water, so space plants to improve air circulation and promote rapid drying of leaf surfaces. When irrigating, avoid wetting the foliage and irrigate in midday to promote rapid drying. Remove fallen diseased leaves. Do not water or fertilize more than is necessary to avoid promoting excessive new growth. Minimize summer pruning which encourages new growth. A fungicide such as Daconil or Funginex can be sprayed starting when new growth begins in the spring with additional applications at 10 day intervals until mid-June. Severely diseased plants should be removed and replaced with a different plant that is not susceptible to leaf spot.

For more information, check out this on-line publication:

Entomosporium Leaf Spot on Red Tip


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Why is my Japanese holly dying?

Japanese hollies are susceptible to a number of problems, including black root rot, nematodes, and drought. Black root rot is a soil-borne fungal disease that is favored by high soil moisture and low soil temperatures. The fungus affects the root system and reduces plant vigor. Symptoms include stunting of terminal growth, leaf yellowing, and in severe cases, dieback. Infected roots are dark brown to black. Diseased plants usually decline over a period of months and frequently die during or following drought periods. Nematodes also cause extensive damage to hollies in the landscape. Damage to plants from root-feeding nematodes can result in poor growth, low vigor, yellowing or bronzing of the foliage, loss of leaves, stem die-back, and eventually death. Submit a sample to your local Extension office for diagnosis of disease or nematodes. Dwarf yaupon holly is more resistant to drought, disease, and nematodes and is considered a good substitute for Japanese hollies.

Instructions for submitting a diseased specimen: Bring a quart of soil along with some roots from the sick plant, as well as a sample of the infected branch and foliage. Try to bring a sample that is showing symptoms but is not totally dead. Keep the soil and foliage samples in separate bags to prevent contamination. It is best to submit samples no later than Wednesday, so that if they need to be sent to the NCSU diagnostic lab, they will arrive by the end of the week (a sample that sits over the weekend often deteriorates so badly it makes diagnosis difficult).

For more information, check out this on-line publication:

Holly Diseases and Their Control in the Landscape


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Why won't my camellia bloom?

Temperature or moisture fluctuation, nutrient problems, poor soil or poor drainage can all result in a poor flowering display in camellias. Camellias perform best planted in areas with uniform moisture that are not too wet or too dry. Freezing temperatures can cause buds to drop before opening. Hot weather during the fall or spring may encourage shoot growth and cause the plant to drop its flower buds. Conduct a soil test to determine nutrient requirements.


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When is the best time to relocate (dig and move) plants in the landscape?

It is best to relocate plants during the dormant season, which means anytime from October to March. It is best to root prune the plant the year before (also during the dormant season) to encourage the growth of a strong root system within a confined area. The publication listed below provides detailed guidelines for root pruning, transplanting, and maintenance.

For more information, check out this on-line publication:

Transplanting Established Shrubs


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What type of plants are good for wet areas?

Consult the publication below for a list of trees, shrubs, and herbaceous perennials adapted to wet sites in North Carolina:

Qualifiers for Quagmires: Landscape Plants for Wet Sites


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What type of plants are good for shady areas? Full sun?

The publication Gardening in the Shade provides a list of plants that perform well in the shade. Drought-Tolerant Plants for North Carolina Landscapes also includes information on plants that do well in both full sun and shady areas (look under the exposure column for sunlight requirements).

For more information, check out these on-line publications:

Drought-Tolerant Plants for North Carolina Landscapes
Gardening in the Shade


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How do I get rid of this stump in my yard?

There are several ways to remove a tree stump. Smaller stumps can be removed with a sharp spade or pick. Larger stumps can be removed with a stump grinder. A local tree service company can perform this service or you can rent a grinder. You can speed up the decomposition process of the stump with stump removal chemicals available at lawn and garden centers. Usually the chemical is poured into holes that have been drilled into the stump and allowed to stand for several weeks. Repeat applications may be necessary. You can let the stump decay naturally. Cut off all new sucker growth before it reaches 8" in height to gradually deplete the stored food reserves. This can take 5-10 years but is easy, inexpensive, and chemical-free. You may decide to include the stump in your landscaping instead of trying to get rid of it. Hollow out the top with a router or drill and use it as a bird feeder. Fill it with water and enjoy the parade of birds and butterflies it attracts. Climbing vines or annuals planted with good garden soil in the stump can turn the stump into a natural container.


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Is this plant poisonous?

Consult the website listed below for photos and descriptions of poisonous plants in North Carolina. In cases of accidental exposure or ingestion, contact the Carolina Poison Center at 1-800-848-6946.

For more information, check out this website:

Poisonous Plants of North Carolina


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How do I control honeysuckle and kudzu?

Round-up and 2,4-D can be used to control honeysuckle and kudzu. Mixtures of 2,4-D, dicamba, and MCPP sold as "brush killers" are also effective. Read and follow all label directions.


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How do I control voles in my landscape beds?

Voles are mice that cause damage in horticultural plantings by eating flower bulbs, girdling the stems of woody plants, and gnawing roots. Voles and moles are often confused. Moles are insectivores, while voles are herbivores, relying solely on plant parts for their nourishment. Both make tunnels. Moles are commonly found in lawns while voles are commonly found in landscape beds. Check for evidence of vole tunnels under mulch. Keep mulch pulled back several inches away from plant stems to reduce protective cover for the voles. Voles can be trapped or poisoned using a registered rodenticide such as Rozol Rat and Mouse Killer Pellets. It is important to read the label carefully for safe application. Household pets should be prevented from coming into contact with the poison or any vole that has consumed the poison. Consult the publication listed below for details.

For more information, check out this on-line publication:

Voles in Horticultural Plantings


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What's the best lawn grass to plant?

There is no "best" lawn grass. It depends on what you want from your lawn, your site characteristics, and how much maintenance you prefer. Fescue, centipede, and bermuda are the three most common turfgrasses in Lee County. You need to decide if you prefer a warm-season or a cool-season grass. Do you have alot of shade? You may want to go with St. Augustinegrass or a fescue/bluegrass mix. If you have children you need a grass that can withstand alot of traffic, such as bermuda. You need to decide how often you want to mow or fertilize, because maintenance needs vary according to the grass you select. The publication listed below contains a great deal of information on the characteristics and requirements of each lawn grass, as well as planting and maintenance procedures.

For more information, check out this on-line publication:

Carolina Lawns


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What type of lawn should I plant if I have alot of shade?

Tall fescue, Kentucky bluegrass, bluegrass/fescue mixtures, and St. Augustinegrass are all good choices for shady lawns in North Carolina. Centipedegrass and and zoysiagrass can also be used but are not quite as shade-tolerant as the others.

For more information, check out these on-line publications:

Selecting and Managing Lawn Grasses for Shade
Carolina Lawns


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How do I control wild onions (garlic) in centipedegrass?

Wild garlic, sometimes called wild onion, appears in winter as ugly green "tufts" of erect shoots standing several inches above your centipede. This weed is one tough cookie for centipede lawn owners. Shoots emerge from perennial bulblets that are impossible to eliminate by digging. The best product for wild garlic control is 2,4-D. Since this herbicide can harm centipedegrass, it can only be applied as a spot treatment and not over the entire lawn area. Apply one tablespoon of 1% 2,4-D solution per garlic clump. By this method, you will limit injury to a four inch diameter circle, which will fill in quickly as your centipede greens up. It may take several years of this ritual to control wild garlic.


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What is causing these tunnels in my lawn?

Moles tunnel in search of insects, earthworms, and beetle grubs. Two general methods are used to control moles. You can reduce mole populations directly through trapping or indirectly by reducing the grubworm population. The best time to trap is in the spring when the first burrows are noticed or after the first fall rainfall. If a trap is not sprung in 2 days, move it into another tunnel.

Soil insecticides such as diazinon can be applied in the spring (April to early May) or late summer through early fall (from August through October) when the grubs are feeding near the soil surface. The timing of the insecticide application is critical if control is to be effective. Pesticides applied any other time will be ineffective. Water the lawn thoroughly after application to move the insecticide down into the soil.

A biological control agent called milky spore disease can be applied for long-term grub control. Milky spore is a naturally occurring bacterium that is fatal to Japanese beetle grubs but harmless to all other organisms. It is applied as a dust or powder and one application can last in the soil for over 10 years. It may take 2-3 years for the spore count to build up enough for maximum results. The larvae become infected with the disease and release billions of disease spores into the soil when they die. This is why milky spore will not spread unless grubs are present in the soil. The more numerous the grubs, the faster the beneficial disease is established in your lawn. Once the grubs are destroyed, milky spore lies viable and dormant in the soil, awaiting more grubs.

For more information, check out these on-line publications:

Controlling Moles in Home Lawns
Controlling White Grubs in Turf


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How do I get rid of sandspurs?

Sandspurs (also called sandburs) are usually noticed after they have set seed and someone has had an encounter with those nasty burs. However, the best time to control sandspurs is on the early spring when they are young and actively growing. The herbicide Vantage provides the best postemergence control of sandspurs in centipedegrass.


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I planted my lawn in the spring, and now it is overrun with weeds. What can I do?

The best defense against lawn weeds is a healthy turf. Many people experience weed problems in newly established lawns because the lawn never got off to a good start. For example, fescue should be planted in the fall in North Carolina but is often mistakenly planted in the spring. The fescue germinates but then doesn't have time to establish well before the temperature rises and inhibits root growth (fescue is a cool-season turf and grows best under cooler temperatures). A hot dry period can severely damage a newly-seeded fescue lawn, rendering it unable to compete with weeds.

A lawn overrun with weeds indicates less than ideal conditions for the turf (but perfect conditions for weeds!). Conduct a soil test to determine lime and fertilizer needs. Check for drainage problems or excessive shade. Correct any problems and allow your turf to produce a dense stand and weed problems will be kept in check. In Lee County, many people have problems with winter annual weeds on a warm-season turf such as centipede. These weeds may be unsightly, but since they are growing at a time when the turf is dormant they are not directly competing with the turf for resources. Therefore they are not causing much harm. Again, optimizing growing conditions for the centipede will promote a dense turf and reduce weed problems in the dormant season.

To control existing weed problems, first identify the type of weed, then select an appropriate herbicide and use it at the right time of the year when the weeds are most susceptible. Most herbicides work best on weeds that are young and actively growing, but usually weeds are noticed after they have already set seed and are at the end of their life cycle. This means that you need to map their locations and be ready with a control strategy early in the season the following year. Call your local Exension office for help with weed identification and herbicide recommendation.


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How do I get rid of moss in my lawn?

Moss problems in lawns are associated with unfavorable conditions for growing healthy turf. Conditions favoring the growth of moss include low fertility, poorly drained soils, acid soils, excessively wet soils, excessive shade, soil compaction, and excessive thatch. If you have a moss problem you need to determine which unfavorable condition may exist and try and correct it. Conduct a soil test to determine lime and fertilizer needs. Plant shade-tolerant turfgrasses. Avoid excessive irrigation and improve drainage. Aerify compacted soils. Increase air movement and light penetration in shaded areas by removing unnecessary undergrowth and pruning tree limbs. If the problem is severe, you may choose to plant a shade-tolerant ground cover instead of turfgrass.


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What is causing these patchy, dead areas in my lawn?

Patchy, dead areas in a lawn can indicate disease, nematode, or insect problems or some type of environmental stress (incorrect pH, poor drainage, etc.). Submit a sample to your local Cooperative Extension office for diagnosis. Cut a patch of turf about one foot square that includes both healthy and diseased foliage. Make sure you cut down far enough to include soil and roots. Place the turf sample in a plastic bag and bring it to the Extension office at the beginning of the week. You might also want to conduct a soil test to determine lime and fertilizer needs. These are available through the Extension Service. Consult the publications listed below for photos and descriptions of some common turf diseases.

For more information, check out these on-line publications:

Diseases of Cool-Season Grasses
Diseases of Warm-Season Grasses


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How and when do I fertilize my lawn?

Fertilizer rates and timing of application vary according to the type of turfgrass you have. Timing of fertilizer application is critical to optimal turf growth. Conduct a soil test to determine lime and fertilizer requirements. Consult the publications listed below for detailed information on lawn maintenance requirements for Carolina lawns. A summary of fertilizer requirements follows:

1) Tall fescue: Follow soil test recommendations for type and amounts of fertilizer. In the absence of a soil test, use a complete nitrogen-phosphorous-potassium (N-P-K) turf fertilizer with a 3-1-2 or 4-1-2 ratio (i.e., 12-4-8 or 16-4-8). Fertilize with 1 lb. of actual nitrogen per 1,000 square feet in mid-September, November, and again in February. Apply lime as recommended by a soil test.

2) Centipedegrass: Follow soil test recommendations for type and amounts of fertilizer. In the absence of a soil test, fertilize with 1/2 lb. of nitrogen per 1,000 square feet in mid-June using a high potassium fertilizer (i.e., 5-5-15, 6-6-12, or 8-8-24). Fertilize with 1 lb. of potash per 1,000 square feet 4-6 weeks before expected frost using 1.6 lbs. of muriate of potash (0-0-60) or 2 lbs. of potassium sulfate (0-0-50). Do not lime centipede unless recommended by a soil test.

3) Bermudagrass: Follow soil test recommendations for type and amounts of fertilizer. In the absence of a soil test, fertilize with 1 lb. of nitrogen per 1,000 square feet several weeks after the grass turns green. In the absence of a soil test, use a complete nitrogen-phosphorous-potassium (N-P-K) turf fertilizer with a 3-1-2 or 4-1-2 ratio (i.e., 12-4-8 or 16-4-8). Apply 1 lb. of nitrogen per 1,000 square feet every 4-6 weeks up until September. In September, 4-6 weeks before the first frost, apply no more than 1/2 lb. of nitrogen per 1,000 square feet. Use a low-nitrogen, high potassium fertilizer such as a 5-10-30. Apply lime as recommended by a soil test.

For more information, check out these on-line publications:

Tall Fescue Lawn Maintenance Calendar
Bermudagrass Lawn Maintenance Calendar
Centipede Lawn Maintenance Calendar
St. Augustinegrass Lawn Maintenance Calendar
Zoysiagrass Lawn Maintenance Calendar


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Frequently Asked Questions about Soil Testing & Fertilizers

Check out the NCDA's webpage:

NCDA Frequently Asked Questions about Soil Testing & Fertilizers


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How and when do I prune my fruit trees?

Fruit trees can be pruned during the summer and during the dormant season. Trees respond very differently to winter (dormant) and summer pruning. Most people prune during the winter. However, if a tree is pruned heavily during the winter, it responds by producing many new, vigorous, upright shoots called watersprouts. Watersprouts are undesirable because they can shade the fruiting wood of the tree and have a negative impact on fruit production. Heavy dormant pruning also promotes excessive vegetative growth at the expense of fruit production. Correct, light dormant pruning can improve the shape of the tree, improve light penetration, and increase fruit production. Dormant pruning should be done after the chance of a hard freeze has past to avoid winter injury. Late February/early March is preferable.

Summer pruning should be combined with light dormant pruning for best results. Summer pruning results in reduced vegetative growth. Pruning should begin after vegetative growth is several inches long. Generally summer pruning is limited to removing the upright and vigorous current season's growth. Use only thinning cuts (removing the entire branch). Do not prune after July.

It is necessary to choose an appropriate training system for your fruit tree. There are training systems that are best suited for a particular fruit crop, but a fruit tree can be trained to any system. Generally, apples, pears, and pecans are trained to a central leader. Peaches and nectarines are trained using the open center system. The publication listed below describes techniques for each type of pruning. Helpful illustrations provide visual aids.

For more information, check out this on-line publication:

Training & Pruning Fruit Trees


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What is causing small tree branches to fall off my pecan tree? It looks like they were sawed off.

A beetle called the twig girdler is likely responsible for this damage. Damage is usually noticed in late summer when twigs and branches fall to the ground, cut as neatly as if by a knife. The adult female twig girdler cuts a small incision through a twig and then inserts her egg into a gnawed hole towards the tip of the twig above this incision. The larva hatches and feeds inside the twig, eventually severing the branch. Winds often cause the branch to fall to the ground. The larva overwinters and pupates inside the twig (even if it has fallen to the ground) and the adult emerges in late summer.

Since the twig girdler larva is inside the twig when it falls from the tree, the best control is to gather and destroy fallen girdled twigs.

For more information, check out these on-line publications:

Pecan Insects and Their Management
Twig Girdler


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Why are my pecan nuts falling early? I have noticed holes in the nuts later in the season.

Pecan weevils are small beetles that insert their eggs inside the nut in early August while it is still on the tree. The pecan usually falls prematurely from the tree a few days later and the larva develops inside the fallen nut, eventually emerging through a hole it has chewed in the shell and overwintering in the soil. The larvae pupate in the soil and adults emerge from August through September. For pecan weevil control, clean up and destroy fallen nuts that house larvae. Liquid Sevin can be sprayed in August on foliage as well as on the ground. You can try applying a strip of duct tape, sticky-side out, around the trunk a few feet off the ground to trap weevils crawling up the bark. The weevils can also fly but the sticky trap will catch some.

For more information, check out this on-line publication:

Pecan Insects and Their Management


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Why aren't my figs producing fruit?

Home gardeners are often concerned when their figs fail to set or ripen fruit, or the fruit drops prematurely. There may be several reasons for this. Excessive fertilization can cause a plant to put all its energy into producing vegetative growth at the expense of fruit production. Root-knot nematodes are often associated with figs and can limit fruit production. It's a good idea to submit a nematode sample prior to planting. Certain Californian figs require a wasp pollinator that we do not have here in North Carolina, so make sure you have a variety that is adapted to local conditions (Celeste and Brown Turkey are good choices). Drought, cold, or heat can also cause fig fruits to drop.

For more information, check out this on-line publication:

Figs


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How and when do I prune my blueberries?

Pruning helps to control the size of the bush and increase fruit size. Pruning initiates new, vigorous growth on which the next year's fruit is borne. Prune the plant back severly at planting, leaving only the strongest 3-4 shoots. Remove 2/3 of the top growth on bare root plants and 1/2 the top growth on container plants at time of planting. During the second year of growth, remove all flower buds and any weak, damaged, or diseased growth. Some flower buds can be left on vigorous shoots the third year. During the first 3 years after planting, cut back excessively tall and limber shoots during the dormant season (late winter) to stimulate branching and strengthen the shoots. If the bush has many old shoots, cut some of them to within a foot of the ground to produce new vigorous shoots. Thin fruiting shoots to reduce the number of flower buds by 50%. On mature plants, remove all canes that are diseased or damaged and cut back tall vigorous shoots in late July to force branching at a lower level and to control plant height.

The Lee Counter Center of the Cooperative Extension Service has a video on blueberry pruning. Call 775-5624 or stop by our office if you would like to borrow it.

For more information, check out this on-line publication:

Growing Blueberries in the Home Garden


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How and when do I prune my grapes?

The key to growing grapes is to unfailingly prune the vines each year. Muscadines are vigorous vines, and unless you whack them back in the dormant season, they will yield few grapes. I do not believe you can hurt a grape vine by severe pruning. Vinifera grapes in Europe are often pruned to pitiful stumps by generations of vinedressers, in ancient, yet still productive, vineyards. On the other hand, to fail to prune inevitably brings a tangled mass of unfruitful, diseased wood.

Pruning should be done in February or early March. Many people become alarmed when the vines "bleed" after pruning, but bleeding does not harm the vines.

Whether you train your vine to a wire, an arbor, a fence, or a Geneva Double Curtain, the principles of grape pruning are the same: first, know where and how the fruit is borne. Grapes clusters arise on new shoots that come from the previous season's shoots only. This year's grapes will come from new wood. This wood will be light tan in color, and will have visible buds where the leaves were attached. This new wood is called a fruiting spur.

Old wood on the grape vine does not bear fruit, but supports spurs which do. Parallel lines of old wood should be thinned to one old branch ('arm' or 'branch' or 'cordon') every 18" or so, along some means of support. Training systems rely on parallel wires or boards spaced evenly to support one, and only one, permanent arm of old wood.

Neglected vines that have been unpruned for several years present a dilemma: you can revive the old arm by shortening it and removing newer competitors, or you can sacrifice the old arm and promote a promising younger shoot. Choose the healthier arm that supports the best looking spurs.

Once you have removed competing arms, prune spurs. Cut back all spurs to one or two buds (4" is an approximate length). You need one spur every 4". Remove the rest. Remove any tendrils girdling vines. In grape vine pruning, the more removed the better.

The Lee Counter Center of the Cooperative Extension Service has a video on grape pruning. Call 775-5624 or stop by our office if you would like to borrow it.

For more information, check out these on-line publications:

Muscadine Grapes in the Home Garden
Growing Grapes in the Home Garden


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What are these spots on my tomato leaves?

Early blight is caused by a fungus that produces leaf, stem, and fruit lesions. Leaf spots can start out brownish-black and then expand to show concentric zones with a yellow halo. Septoria leaf spot is another fungus that produces symptoms characterized by numerous small gray or yellow circular leaf spots with dark borders, and may have yellow halos. The fungus that causes gray leaf spot produces angular-shaped lesions.

Once a disease is present, your only option is to slow the rate of disease transmission. Scout your garden regularly and remove infected leaves or plants because they provide inoculum for the disease to spread. Don't plant your tomatoes in the same spot you planted them last year. Fungi can overwinter in the soil and be ready to pounce the next time you plant an unsuspecting tomato seedling. Many diseases are host-specific to tomatoes and will not infect unrelated species (hint: tomatoes, peppers, potatoes, and eggplants are all related species). Splashing water can help spread fungal diseases, so only water the root zone of the plant and avoid wetting the foliage. Mulching and staking can help reduce the splashing effects of rain or irrigation.

Unlike soil-borne diseases which infect stem tissue, foliar diseases don't normally kill the plant but they can decrease yield. Fungicides that contain chlorothalonil or mancozeb can be used to control leaf spot diseases. Make sure that the product you select lists tomato on the label, and follow label directions carefully. Organic gardeners can use a copper compound such as a Bordeaux mixture as a fungicide.

For more information, check out this on-line publication:

Diseases of Home Garden Tomatoes


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What is causing my tomato to wilt?

The primary diseases that cause wilting are southern blight, southern bacterial wilt, and tomato spotted wilt. The first above-ground symptom of southern blight is plant wilting, which is caused by stem rot at the soil line. Small, mustard seed-sized sclerotia (reproductive structures) form on the lower stem.

Southern bacterial wilt is more common on tomatoes later in the season. It is characterized by sudden plant wilting in the absence of leaf yellowing. Late blight can be a problem later in the season in wet weather.

Tomato spotted wilt is a virus that is transmitted by tiny insects called thrips that feed on infected leaves. Symptoms of tomato spotted wilt virus include leaf discoloration, necrosis (dieback) of upper branches and leaves, and eventual collapse of the entire plant. There may be some wilting.

In any disease control program, the first line of defense is prevention. Employ proper cultural practices to ensure the healthiest, most vigorous plant possible. A non-stressed plant is better able to resist pests and disease-causing pathogens. Resistant varieties can provide control of some diseases including verticillium wilt, fusarium wilt, and tobacco mosaic virus. Currently, there are no good varieties resistant to southern bacterial wilt, southern blight, or late blight.

Once a disease is present, your only option is to slow the rate of disease transmission. Scout your garden regularly and remove infected leaves or plants because they provide inoculum for the disease to spread. Don't plant your tomatoes in the same spot you planted them last year. Fungi can overwinter in the soil and be ready to pounce the next time you plant an unsuspecting tomato seedling. Many diseases are host-specific to tomatoes and will not infect unrelated species (hint: tomatoes, peppers, potatoes, and eggplants are all related species). Splashing water can help spread fungal diseases, so only water the root zone of the plant and avoid wetting the foliage. Mulching and staking can help reduce the splashing effects of rain or irrigation. If the disease is transmitted by an insect, control of the insect vector is important. Unfortunately, it is extremely difficult to control thrips, especially if you are a home gardener. Discard the infected plants along with their thrips vectors by placing a large trash bag over the infected plant and removing it.

For more information, check out this on-line publication:

Diseases of Home Garden Tomatoes


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What is eating the leaves of my eggplant? The leaves have a shot-hole appearance.

The eggplant flea beetle is a tiny (1/10" long) beetle that chews very small, rounded holes in leaves, causing a shot-hole appearance. The adult flea beetles overwinter at the edges of fields and start out feeding on weeds in the early spring before migrating to vegetables. Keeping fields free of weeds helps control beetle populations. Later plantings of eggplant gives the crop a competitive advantage over the flea beetles. Destroy plant residues at the end of the season to discourage beetles. Keep areas surrounding beds clean to reduce overwintering sites. Floating row covers can be used to to prevent damage. Sevin and malathion are labeled for use on eggplant to control flea beetle. Follow all label instructions.

For more information, check out this on-line publication:

Flea Beetles on Vegetables


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How come my squash and cucumbers are not developing fruit?

There are a number of reasons cucurbit crops like squash and cucumbers fail to produce adequate fruit set. Poor pollination is a possibility. Members of the cucurbit family (i.e., squash, cucumbers, melons, etc.) produce male and female flowers. These crops rely on bees to carry pollen from the male flowers (which bloom first) to the female flowers. Anything that interferes with pollination reduces fruit set. Cold, rainy weather reduces bee activity. Improper use of pesticides can kill bees. Use caution with pesticide applications at all times, especially during bloom. Follow all label instructions. Many home gardeners rely heavily on Sevin Dust, but it is death to bees. They mistake it for pollen and take it back to the hive where it can have devastating effects. If Sevin is to be used, apply it in liquid form. Fertilization can also contribute to poor fruit set. Too much fertilizer can lead to excess vine growth at the expense of fruit production. Too little fertilizer can cause fruit to abort.


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What is causing my squash plants to wilt?

Squash vine borers are small, whitish caterpillars that tunnel into stems at the base of plants and feed inside the vine, eventually causing the plant to wilt. The adult moth lays its eggs on the stem in May or early June, and the larvae hatch about a week later and immediately tunnel inside the stem. A vigilant gardener will notice entry holes at the base of the plant, surrounded by yellow, sawdust-like droppings. When the droppings are noticed, slit the vine with a sharp knife and remove the larva. Cover the injured area with moist soil so the plant can re-root. The plant's chances of surviving such "surgery" are much greater if the borer is removed early, before it has had a chance to tunnel very far. If you really want a challenge (and you have good eyes!), keep an eye out for the very tiny reddish-brown eggs laid at the base of the stem in May/early June. If you see them, simply rub them off. The pesticide Thiodan is labeled for use on home garden squash. Plants must be treated before first bloom. Once the borers have entered the stem, the pesticide is ineffective.

For more information, check out this on-line publication:

The Squash Vine Borer


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Why are the bottoms of my tomatoes rotting?

One of the most disheartening things in the garden is a tomato that looks beautiful from above, but, when picked, has a sunken black spot on the underside near the blossom scar. This spot begins as a tan area at the blossom end that expands and decays as the fruit ripens. Blossom end rot is a tomato nutritional disorder. The culprit is not a fungus or bacteria, but a lack of calcium during fruit development. No amount of fungicide application will cure this problem.

Even if calcium levels are ample in the soil, the tomato plant may have trouble extracting calcium. Calcium forms salts that don't dissolve readily, and if they aren't dissolved in soil moisture, the roots can't get them. Also, even after the plant has gotten enough calcium to make healthy plant growth, it cannot move calcium from the stems and leaves to put it to use in the developing tomato fruit.A plant will need to be able to pull new calcium from the soil throughout the growing season to supply the developing fruit. Incidentally, this is also why peanuts sometimes develop "pops", those well-developed shells that disappoint you with no peanut within. Farmers add gypsum (calcium sulfate) at flowering to supply the "pegs" of developing peanuts in the soil.

The remedy for blossom end rot includes five important steps. First, maintain adequate calcium levels in the soil by applying enough lime to maintain the pH levels at 6.5 to 6.7 (lime supplies calcium, and by raising the pH, calcium is made more available). Second, do not apply too much fertilizer at one time once the plants have started to bear. One cup of 10- 10-10 per 10 plants is enough to apply at one time (every four weeks). Third, mulch your plants to maintain even moisture. This will allow the calcium to continue to move from the soil to the plants even in drought. Fourth, thoroughly water your plants weekly in any week where less than 1.5 inches of rain has fallen. Last, in real problem situations, you can use calcium nitrate or calcium chloride sprays on the leaves every two or three days. Four tablespoons of either material per gallon of water is the rate to use.

For more information, check out this on-line publication:

Blossom-End Rot of Tomatoes in the Home Garden


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When do I plant tomatoes, peppers, etc., and what are the best varieties to use?

Consult the on-line publications below for planting dates and variety recommendations:

Planting Dates For Vegetables
Vegetable Fact Sheets


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How do I know when my watermelons are ready to harvest?

Ripe watermelons produce a dull thud rather than a sharp, metallic sound when thumped. Other ripeness indicators are a deep yellow rather than white color where the melon touches the ground, brown tendrils on the stem near the fruit, and a rough, slightly ridged feel to the skin surface.

For more information, check out this on-line publication:

Harvesting Vegetables


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How do you get rid of aphids in the vegetable garden?

Aphids, often called plant lice, are slow-moving, soft-bodied insects that are considered pests on a number of local landscape and garden plants, including crape myrtles, gardenias, roses, camellias, euonymous, maples, apples, conifers, and a number of vegetables. Aphids damage plants directly and indirectly. They feed on the undersides of leaves by inserting piercing mouthparts into the plant and sucking out sugar-filled sap. The saliva they inject as they feed can cause curled or distorted plant growth and reduced vigor. Honeydew, the sticky-sweet excretions of aphids, forms on infested leaves and promotes the growth of sooty mold, an unsightly fungus that can potentially interfere with photosynthesis. Aphids may also transmit destructive viruses.

We have many species of aphids here in North Carolina. Amazingly, female aphids are able to reproduce without mating, a process called parthenogenesis. These females give birth to live young during the growing season, with young aphids reaching maturity in about 10 days. Both winged and wingless forms are produced. Many species in North Carolina also overwinter in the egg stage.

Aphids have many natural enemies, including green lacewings adults and larvae, hover fly maggots, parasitic wasps, some fungi, and -- the most familiar to home gardeners -- the beloved lady beetles, also called ladybugs. Both lady beetle adults and larvae feed on aphids and other pests such as mealybugs, scale insects, and spider mites. Given their important role as predators, lady beetles should be protected and encouraged in the home landscape. When aphid problems are out of control, it probably means that there are not enough lady beetles and supplemental control measures should be implemented. You can purchase lady beetles to release in your landscape, although there is no guarantee they will stick around to take care of your aphid problem (at least someone's garden is sure to benefit!). Improper use of pesticides can reduce beneficial insect populations, so use pesticides with caution.

Insecticidal soaps and horticultural/summer oils, available at nurseries and garden centers, provide good control of aphids and do not leave a toxic residue, which means they should not harm lady beetles if used correctly (follow label directions for proper use). Recent research has shown that homemade insecticidal soaps can damage plants (which makes sense because liquid dishwashing soap was never intended to be sprayed on plants!), so use these with caution. Make sure the soap or oil reaches the undersides of the leaves where the aphids feed. One application is usually sufficient to knock down the aphid population, then the lady beetles can come in and finish off the rest. Because aphids are fragile insects, you can also control their numbers by spraying your landscape plants with a forceful stream of water directed at the undersides of the leaves. This strategy is not recommended for tender plants, as they may be damaged.


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How do you cure sweet potatoes?

Sweet potatoes should be cured to heal wounds and to convert some of the starch in the roots to sugar. The optimal conditions for curing are to expose the roots to 85 degrees F and 90 percent humidity for one week. Few home gardeners can supply these conditions, so place the sweet potatoes in the warmest room in the house, usually the kitchen, for 14 days. No curing will occur at temperatures below 70 degrees F.

After curing, store the sweet potatoes in a cool location. Never expose them to temperatures below 50 degrees F and never refrigerate them. Temperatures below 50 degrees F will result in "off" flavors and possibly rot the sweet potatoes. Sweet potatoes can be stored under good conditions for over six months.


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What can I do about all these ladybugs in my house?

Asian lady beetles often congregate on the sides of houses in the fall because they are attracted to bright colors. They can gain entrance to the inside of the house through small cracks or through open doors. The beetles may hibernate inside walls but on warm days they may be become active and move about on windows, light fixtures, and ceilings. They move outdoors again in the spring in search of food. If you are experiencing a beetle invasion, your first strategy should be to seal up any cracks to prevent entry. You can vacuum up beetles and then empty the bag outside under a protected area so the beetles can find another overwintering site. Remember that ladybugs are beneficial insects (at least as long as they are outdoors!) and do us a favor by eating aphids and other pests. Another reason to be prompt about emptying your vacuum bag is because decaying ladybugs emit a strong odor that may persist inside the bag for months afterwards.

For more information, check out this on-line publication:

Multi-Colored Asian Lady Beetles


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Help! I am being invaded by millipedes inside my house!

Millipedes sometimes invade buildings, usually when outside conditions are dry or excessively wet. While millipedes are not exactly welcome inside our homes, they do not bite, sting, or transmit diseases, nor do they infest wood, clothing, or food. They feed primarily on decomposing vegetation and are attracted to cool, moist environments such as mulched flower and shrub beds, under leaf litter, stones or logs. They can enter homes through any tiny crack or crevice. To reduce the number of millipedes seeking shelter in your home, minimize moisture and hiding places, especially near the foundation. Keep mulch 6-12" away from the foundation and remove any possible hiding places along the perimeter. Keep water from accumulating near the foundation and reduce the humidity in basements and crawl spaces. Seal cracks and openings in the foundation wall and around doors and windows. Millipedes indoors can be removed with a broom or vacuum.

For more information, check out this on-line publication:

Controlling Millipedes In and Around Homes


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How do I get rid of crickets inside my home?

Extremes in weather conditions, i.e, excessive rainfall or extended periods of hot, dry weather, often brings complaints of camel crickets invading homes. Like many insect pests, camel crickets are attracted to harborage sites, i.e., cool, moist areas in and around the home. Although pesticides can help reduce the nuisance problems with camel crickets, they are not a long-term solution. Effective control starts with removing harborage sites and by excluding these insects from our homes:

1. Caulk or seal gaps and openings around window frames, doors, foundation and clothes dryer vents, soffits, as well as heating/AC and plumbing lines.

2. Install weather-stripping along the bottom of house and garage doors so that it fits tightly against the threshold.

3. Stack boxes and other items off of the ground and away from the walls in a garage or storage building. This helps improve airflow and makes it easier to check for crickets and other pests, including termites.

4. Reduce moisture indoors and in the crawlspace and attic. This usually involves improving ventilation.

5. Keep leaf mulch and wood/bark chips at least 12 inches or more away from the foundation.

6. Keep ground cover and shrubs away from the foundation and siding.

7. Keep firewood stacked away from the house.

8. Remove piles of lumber or other clutter that attract crickets and other pests.

9. Place sticky boards, such as those used for cockroaches and mice, in corners and behind appliances to catch crickets that enter your home.

Pesticides applied outdoors to foundation walls, around vents, crawlspace accesses, basement doors and windows, and insecticidal baits applied along the perimeter can be quite effective unless there are heavy rains. Diazinon, Dursban, and boric acid baits are labeled for use outdoors for camel cricket control. Read and follow all label instructions.

For more information, check out this on-line publication:

Camel Crickets


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What are these bees that burrow into the wood on my house?

Carpenter bees are large black and yellow bees that bore through wood to construct nests. Unlike termites, carpenter bees do not eat wood but excavate tunnels for nesting sites. Wooden decks and overhangs are a prime target, and you can often find sawdust below the hole that has been excavated. Females can be seen busily drilling tunnels in the spring and early summer. The females forage for pollen and bring it back to the nest where they build a pollen ball that the larvae will eventually consume. Carpenter bees are capable of stinging, but rarely do so unless confined in your hand or are highly agitated.

Carpenter bees do not cause serious structural damage to wood unless large numbers of bees are allowed to drill many tunnels over successive years. Woodpeckers may damage infested wood in search of bee larvae in the tunnels. In the case of thin wood, such as siding, this damage can be severe. Holes on exposed surfaces may lead to damage by wood-decaying fungi or attack by other insects, such as carpenter ants.

Nesting activity may be substantially reduced by treating the entrance holes with an insecticidal spray or dust. Sevin dust can be applied into and around the hole and then the hole must be plugged with wood plugs, putty, or stainless steel wool. Avoid inhaling the insecticide or contaminating your clothing with the dust. Always stand upwind from the surface you're treating. Since abandoned tunnels may serve as overwintering sites, or be re-used next spring, it is important that they be plugged with wooden dowel or wood putty.

For more information, check out this on-line publication:

Carpenter Bees


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How can I prevent woodpeckers from drumming on my house?

Woodpeckers hammer to attract mates, to establish and/or defend a territory, to excavate nesting or roosting sites, and to search for insects. Wooden shingles, cedar or redwood siding, metal or plastic guttering, television antennas and light posts are selected as drumming sites because these materials produce loud sounds.

Woodpecker damage can be prevented or eliminated with several techniques including visual repellents, loud noises, and exclusion. Take immediate action to reduce damage because woodpeckers are not easily driven from their territories or pecking sites once they are established. Large holes serve as visual attractants to woodpeckers and should be promptly repaired. Cover the holes with aluminum flashing, tin can tops or metal sheathing, and paint them to match the siding. If damage occurs near areas that provide perch sites, eliminate these sites with metal flashing or other materials. If a single board on the house is serving as a toe hold, heavy fishing line or stainless steel wire can be tightly stretched approximately 2 inches outward across the landing site. Hawk sillhouetes, rubber snakes, mirrors, aluminum pie pans, metal strips, or any other material that may flash or scare can be attached to the house where damage has occurred.

Some woodpeckers are frightened away with persistent loud noises such as banging pots and pans together, firing toy cap guns or yelling. Other woodpeckers are discouraged by deadening the sound-producing area by filling the hollow space behind the wood.

Woodpeckers can be excluded from damage sites under the eaves by attaching hardware cloth or plastic netting to the eaves, angling it back to the siding below the damaged area, and astening it securely. Alternately, fasten the netting under the eaves, stretch down the side of the ouse 3 inches from the siding, and securely attach close to the ground. Woodpeckers are a federally protected species, so a federal permit is required before any lethal control methods can be employed. Penalties and fines are assessed to violators.

For more information, check out these on-line publications:

Prevention of Woodpecker Damage
Woodpeckers


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What are these bright red bugs I'm finding found outside in my yard, around trees and mulch, and on the house?

Adult boxelder bugs are black and with red markings, and about 1/2 " long. The young bugs (nymphs) are bright red. These bugs feed on a number of shade trees and shrubs, and can become a household pest. In fall, boxelder bugs tend to congregate on buildings and enter cracks and crevices to overwinter. They do not bite people or harm goods, but their presence is a nuisance. On warm winter days, the insects become active and move about in and on buildings and cause concern for the homedweller.

Boxelder bugs that find their way inside a home can be swept or vacuumed up. Pesticides such as Sevin, Orthene, and malathion can be applied for control outdoors, but is rarely warranted because boxelder bugs are not usually considered a serious pest of ornamentals.

For more information, check out this on-line publication:

Boxelder Bugs


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How do I control ticks around my home?

How can you protect yourself from ticks? If possible, avoid walking through uncut fields, brush, and other areas likely to harbor ticks. Walk in the center of mowed trails to avoid brushing up against vegetation. Wear long pants tucked into socks and tuck your shirt into your pants. Light-colored clothing makes tick detection easier. Insect repellants can be applied to exposed areas. Keep grass mowed and clear overgrown vegetation from the edges of your property.

Pesticides can be used to control severe tick infestations in outdoor areas around the home. Sevin and Dursban are labeled for tick control in the home landscape. Apply the pesticide uniformly according to label directions and make sure to keep children and pets away until the treated areas have dried.

If you have been in a tick-infested area, inspect yourself and your pets twice a day so that you can reduce the chance of a tick becoming attached. The longer a tick is attached, the greater the chance it can transmit disease. Control ticks on your pets using a tick collar or some other method recommended by your veterinarian.

If you find an attached tick, DO NOT try to dislodge it with a match or cleaning fluid or any other home remedy. This will certainly kill the tick but will make it difficult to remove the tick intact. Disease organisms can escape a ruptured tick and cause infection. Using tweezers or your fingers (protected with a tissue), grasp the body of the tick and pull directly away from the point of attachment with gradually increasing force until the tick is free. Do not jerk or twist as this may cause the tick's mouthparts to break off in the skin. Wash the bite area with soap and water and apply an antiseptic. Mark the date of the bite on a calendar so that if you develop symptoms of Rocky Mountain Spotted Fever or Lyme disease, you will be able to tell your physician when you were bitten. You can also save the tick in a vial of alcohol in case identification is required.

Symptoms of Rocky Mountain Spotted Fever include headache, fever, chills, pains, and nausea. Sometimes a rash appears on the wrists and ankles. Lyme disease develops in three stages. Stage I involves rash and flu-like symptoms such as fatigue, headache, stiff neck, and muscle ache. A rash may develop at the site of the tick bite in some (but not all) patients. Stage II includes cardiac and neurological symptoms such as dizziness, shortness of breath, irregular heartbeat, and brain and nerve inflammation. Arthritic problems may develop during Stage III. The important thing to remember is that both of these diseases can be treated effectively with antibiotics if they are diagnosed early, so be aware of the symptoms and record all tick bites.

For more information, check out this on-line publication (see last section on Mosquitoes and Ticks):

Biting and Stinging Pests


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How do I get rid of wasps and yellowjackets in my yard?

Yellowjackets, in particular, may be late season pests around picnics, trash cans, and humming bird feeders as they scavenge. The only way to control this situation is to locate and destroy the nest, which is rarely possible. As an alternative, keep all outdoor food and drinks covered, except while actually eating. Bee guards or a coating of petroleum based chest rub can be used on hummingbird feeders where the insects land. Trash cans should be kept covered or have a flap over the opening. Defensive behavior occurs in response to nest defense. If the nest is not in the immediate vicinity the likelihood of stings is greatly reduced.

The first decision to make is whether control is actually necessary. Two points to remember:

1) In spite of their reputations, wasps and yellowjackets are actually beneficial because they prey on many insects that we consider to be pests of the shrubs and flowers around our homes. They also serve as food for other bears, skunks, birds, and other insects.

2) Unlike honey bees, hornet and yellowjacket colonies die out each year. Most wasps die out in the fall, but some females overwinter. Nests vacated in the fall are not reused the following year.

If a nest is located where people may be stung or if you (or others) are hypersensitive to bee/wasp stings, then colony destruction may be appropriate. Here are some points to consider as you decide how to approach the problem:

Control is best achieved by applying a pesticide directly into the nest opening. This can be done at anytime of the day, but near dusk most of the wasps are more likely to be inside the nest. You can use any of the aerosol "Wasp & Hornet" sprays that propel insecticide in a stream about 10-12 feet. Direct the spray into the nest opening and then move away from the area in case any of the wasps emerge from the nest. You may need to repeat the treatment on the following evening. For wasps, if the nest is just beginning with a single queen, a broom may be all that is needed to knock it down.

For more information, check out this on-line publication:

Hornets and Yellowjackets
Paper Wasp Control
Reducing the Likelihood of Stings During Outdoor Activities


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Is this an ant or a termite?

There are several kinds of ants that may occur in and around the home ranging in size from about 1/32 to 3/4 inch long and colored yellowish, light brown, reddish-brown, brownish-black or jet black. Ants, as all insects, have three body parts, head, thorax, and abdomen. Most are wingless, but the homeowner sometimes may confuse swarming, winged ants with swarming, winged termites, causing alarm. Ants can be easily distinguished from termites by several characteristics:

1) Ant bodies appear constricted or pinched in at the waist (shaped like a figure 8), while termites do not have the waist constriction.

2) Ants have elbowed antennae, while termites have straight, bead-like antennae.

3) The forewings of ants are much larger than the hindwings. Termites' wings are equal in size and shape.

4) Ant wings are transparent or brownish, while termite wings are milky-white or grayish and longer than the body.

5) Ant wings are firmly attached, while termite wings are easily removed or shed (fall off).

For more information, check out these on-line publications:

Ants In and Around the Home
Biology and Control of Subterranean Termites


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How do I control fire ants?

Fire ants are easy to recognize from the mounds of soil they excavate. The ants themselves are nondescript, small reddish-brown ants. Fire ant mounds, on the other hand, can be spectacular, rising like low, earthen barrows throughout an infested pasture or lawn. There are no visible entrance holes in the mound, and it is normally located in a sunny spot. These mounds can be 18 inches tall, and are composed of fine grains of soil, with no pebbles or coarse grains, with large tunnels arranged inside in an impressive network. When the mound is disturbed, fire ants "boil" out of the nest with fury and intensity, seeking to destroy the threatening menace that dares to disturb their colony.

Control can be achieved if you know how. Unfortunately, many commercial pesticide formulations offer poor control, even though they are marketed for fire ants. There are two effective tactics:

Mound drenches: mix a liquid formulation of Dursban, diazinon, or Sevin with water in a bucket or other container. Use the amount of insecticide the label specifies (usually 1 or 2 tablespoons per gallon of water). Drench the mound and the surrounding soil within 1 or 2 feet of the mound in order to seal off the ants' escape route through side tunnels. How much solution you need depends on the size of the mound. You will need 1 gallon of solution for every six inches of mound diameter. Keep children and pets away until the mound dries. The treatments are most effective when the temperature is below 80 degrees F and the weather is sunny.

Baits: slow-acting baits can be used to take advantage of the ants' foraging behavior. They work when the ants deliver the baits into the mound and feed them to the queen and brood. The baits (Amdro, Award, or Logic) are broadcast at very low rates (about 1 pound per acre), and will kill both native and fire ants in the area. This is a slow- acting but very effective way of killing large numbers of mounds over a certain area. Baits should not be used over an area with just one or two mounds, since the native ants (which compete with fire ants) will also be eliminated, resulting in a rapid re-invasion by fire ants. Baits are fickle: they must absolutely be fresh and dry, because when they are rancid they won't be taken up by the foragers. They are most effective if no rain or irrigation falls for at least 48 hours after application. Baits degrade rapidly in sunlight or dew, so apply them in late afternoon or evening to extend the window of time when they will work.

A useful strategy is to combine both tactics. Spread the baits first without disturbing the mounds. Wait three days, then drench the mounds. Research from Texas and Florida has concluded that this offers the most effective long-term control using current methods. Our local NCDA fire ant technician has also reported success with Orthene tracking powder which is sprinkled outside the mound and then "tracked" back into the mound by the foraging ants. Parasitic flies are currently being experimentally released in North Carolina to test their effectivenes as a biological control agent for fire ants. Hopefully this research will provide more control options in the future.

For more information, check out this on-line publication:

Control of the Red Imported Fire Ant


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This page was created by Debbie Roos, Agricultural Extension Agent, Chatham County Center.

It was last updated on February 19, 2001.

  Please send any questions or comments regarding this webpage to Rhonda Gaster, or call her at (919) 775-5624.