We are on the borderline of being too hot for a lot of plants and too cold for a lot of others. And our abrupt temperature changes make it hard on the rest. We are never quite sure when winter has arrived in Cumberland County; summer might return the next day.
Gardening in Cumberland County CAN be
successful
Of the many aspects of gardening in Cumberland County, an understanding of our soil is probably the most important. Every "transplant" gardener to the county needs a crash course on managing sandy and clay soils.
We live in the Sandhills and Coastal Plain regions, a geological formation which includes parts of Hoke and Cumberland counties. Our soil was prehistorically formed from weathered sandstone and shale. Most of Cumberland County, especially the southern part, is comprised of the soil type called White Store. Characteristic of White Store soil is its very firm clay base (subsoil), the chief limitations being poor drainage and high shrink-swell potential. (Soil cracks when dry, and so may your home's foundation). Soil scientists describe our soil as very sticky, strongly acidic, and highly erodible.
Poor drainage is responsible for many of our planting failures. Test your drainage by doing a "perk test" when the soil is neither extremely dry nor extremely wet. Dig a hole in your yard about 12" deep and fill it with water. Check it regularly for the next 24 hours. If the test hole drains in 3-4 hours you have good drainage; 5-12 hours means moderate drainage, and plants susceptible to root rot diseases must be planted "high"; 12-24 hours indicates that you should "plant high", meaning plant "on" rather than "in" the ground. If you are in doubt about adequate soil drainage, plant "high."
The top 8"-10" of soil determines the success of your gardening efforts. Plants need oxygen just as people do. Clay soil is too compact to allow much "breathing." By adding organic materials to the soil you lighten the texture and thus discourage compaction, add nutrients, improve drainage, regulate soil temperature, and provide needed pore space which is essential to plant growth. Clay without organic matter is like a flattened deck of playing cards. The organic material that you add tips up the "flat" cards, and permits water and oxygen to enter the soil.
To determine the exact amounts of lime and fertilizer your soil needs, have your soil tested, at no cost, by the NC Department of Agriculture. The Cooperative Extension Service Office will provide you with the materials necessary for a soil test. If you have a lawn or garden in Cumberland County, you need to apply lime regularly. Acid soil can be "sweetened" with lime inexpensively. Plants cannot use nutrients that are already present if the soil is too acid, so liming can be just as important as fertilizing. Dolomitic lime is the best garden value you will find for the money. The natural pH for this area is 4.8 to 5.3. Most lawns, vegetables and flowers prefer the 5.8 to 6.5 range. Optimum pH for shrubs and trees depends on the species selected.
Do not work in clay soil when it is wet. Mowing wet lawns or working in wet flower and vegetable beds compacts the soil further and spreads diseases.
Plant only native plants or use varieties adapted to this area. "Imported" plants (such as the ones you had in your former yard) require much more care and pesticides and have less chance of surviving than do native plants. Depending on the area from which you came, you may have to alter a number of your former gardening practices and plant selections.
To improve soil texture inexpensively:
Should you decide to purchase soil amendment material, buy the smallest grind of pine bark mulch or pine bark chips that you can find. Pea-size is ideal but has been difficult to find except when ordered by truckload. However, lately an acceptable size is being marketed as "pine bark soil conditioner" and sometimes as "pine bark mulch." There is much variation within brands and names of products so look before you buy. Pine bark has the advantage of being a native plant material. Peat moss and sand are NOT recommended for use as soil amendments. Buying topsoil is more expensive and is not necessarily better than using other organic materials. Should you use it, the new soil should not be placed on top of existing soil but must be mixed thoroughly with the native soil. More detailed information on soil amendments is available from the Cooperative Extension Service.
Many folks mistakenly believe that digging a planting hole 3 or 4 times larger than needed, adding crushed rock to the bottom and rich topsoil as a backfill will solve all drainage problems. For a long time, this was the recommended planting method. Research has shown that holes dug in poorly drained clay soil will only fill with water and continue to hold this excess water over a long period of time, regardless of the size of the hole. When soils are saturated, the amount of oxygen available to plant roots becomes very limited. This method creates a "bathtub without a drain" and the plants ultimately drown. This traditional planting method is the one usually shown on plant labels, but it is not appropriate for the Cumberland County area unless your perk test tells you otherwise.
"High Planting" of Shrubs:
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For more than one bush, prepare the entire bed. Till or break up the soil. Dig a very shallow saucer or plant on top of the existing soil, with 1/3 to 1/2 the rootball above ground level. Gently loosen and spread roots around in the saucer. BACKFILL: To 2/3 native soil add 1/3 organic matter, lime if indicated, plus 1-2 TBS. Superphosphate per plant (no other fertilizer), and mix thoroughly. MULCH; Cover with 3-4" of pine straw, mulch or nuggets. WATER well. High plantings dry out faster than traditional plantings but their survival chances are better. Pay close attention to watering until plants are well established. |
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Planting Trees:
Recent research from the American Forestry Assn. has taught us that major changes are needed in the way we have traditionally planted trees. Instead of digging a hole, mark off a planting area at least 5 times the diameter of the planting ball. The bigger the better. With shovel or rototiller, loosen and break up the soil in the area to a depth of 12", adding lime if indicated. If planting a field-grown tree, do NOT amend the soil. If the tree roots cannot live in our native soil, the tree cannot survive here. If planting a container-grown tree, you may amend the soil with the same material that was in the container, as long as you mix it uniformly throughout the area, using no more than 1/3 amendment material to 2/3 native soil.
In the center of the prepared area, dig a shallow saucer to set the tree. Sit the root ball on solid ground, with the upper surface level with the existing soil. Backfill around the root area, using water instead of your foot to settle the soil and prevent major air pockets. Cover the entire area with 2-4" of mulch. Keep tree watered well for the first year. More detailed information on the new way to plant trees is available from the Cumberland County Cooperative Extension Service.
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