Often homeowners attempt to grow flowering potted plants after they finish flowering. While this is possible for many plants, other plants should be enjoyed while they are in flower and then thrown away.

African violets - are excellent indoor flowering plants. They produce flowers year round if given proper growing conditions. Check plants carefully before purchasing since pests and diseases spread very easily among other violets. Be especially watchful for crinkled tight crowns -- a possible sign of incurable cyclamen mites.

Maintain night temperatures between 65°F and 70°F; the temperatures should be 10 degrees warmer during the day. African violets prefer good light (but not direct), moist soil (allow to dry slightly), and high humidity. Poor flowering is often related to insufficient light. East and west facing window sills are the best locations. African violets are highly susceptible to root and crown rot if overwatered. Use warm or room temperature water since cold water can cause spots to develop on the leaves.

Amaryllis - bulbs will normally flower within six to eight weeks of planting. Place in bright light; direct sunlight can shorten the life of the flowers. The soil should be kept constantly moist; excessive drying will reduce flower life and cause the flower stalk to bend.

After the flower fades, cut the stem off just below the faded flower. For maximum bulb development, keep plants actively growing after they finish blooming. They prefer bright light to full sun, with a night temperature above 60°F. As soon as danger of frost has passed, set the plants in the garden in a semi-shaded location. In the fall, you can leave the bulbs in the ground or bring the plants back indoors to bloom again. Stop watering to allow old growth to die back, and store them in a cool, dark place to rest. They will be ready to force again about November 1. Place them into a warm, well lighted room and water moderately to begin new growth.

Azalea - Keep the plant in a well lighted location, but avoid direct sun while in flower. A night temperature between 55°F and 60°F will prolong flowering. Keep the soil uniformly moist; do not use softened water. Greenhouse azaleas are not hardy outside and should be discarded after flowering.

Calceolaria and cineraria - thrive in cool temperatures. Locate the plant in a cool room where temperatures are near 50°F to 55°F at night. Provide bright light but not direct sunlight. Excessive heat or dry soil can cause rapid decline. Keep the plant well watered with slight drying between waterings. After flowering is completed, the annual plants will gradually decline and can not be reflowered.

Christmas pepper - The fruit will be at peak color for one to two months. They will be brighter and last longer if you provide high light, mild temperatures (60°F to 75°F), and keep the soil moist. Fertilize weekly with a soluble fertilizer. The plant can be set outdoors after the danger of frost has past.

Chrysanthemum - Buy chrysanthemums when flower buds first show full color. Diffuse, bright light (but not direct sun light) and 60°F to 70°F temperatures will prolong peak bloom. Water often enough to prevent the leaves from wilting. Two types of mums are sold at retail outlets: pot mums (killed by frost) and garden mums. Garden mums are generally available in the fall as flowering pot plants. They can be planted outdoors and are hardy through the winter. Garden mums are perennials and will flower each year. Pot mums are greenhouse cultivars; they provide three to four weeks of enjoyment and should be discarded after flowering, as they are difficult to reflower.

Cyclamens - require bright light and a night temperature between 50°F and 55°F. Day time temperatures are less critical but should not exceed 70°F. Cyclamen is a heavy user of water and must be watered whenever the soil surface is dry. Flower buds will fail to develop if the night temperature is too high or if light is poor.

After flowering, gradually withhold water until the foliage dies back. This begins a rest period. Do not water for six to eight weeks. By mid-summer, begin watering gradually. As new leaves develop, move the plant to a sunny location and resume normal watering and fertilization.

Easter lilies - are grown specifically to flower for the Easter season. Choose strong-stemmed plants with evenly distributed foliage and four or more flower buds. Cool temperatures (55°F to 60°F) prolongs flowering. Keep the plants moist but avoid over watering. Keep the plant in a bright location but avoid full sun and drafts. Remove yellow stamens before the pollen sheds to make the flowers last longer and to keep pollen from staining clothing and furniture. Cut off faded flowers as they collapse. Easter lilies can be transplanted outdoors in most areas in North Carolina and will often rebloom the following June. It's difficult to reflower bulbs kept in pots.

Spring-flowering bulbs - To get the most color and greatest longevity from your spring flowering bulbs, buy plants when the flower buds first show color. Keep plants cool (60°F) to slow down flower development and to prolong the flower's life. They will tolerate temperatures down to 40°F. Keep plants well watered as water stress can cut the flowering time in half. Do not place them in a sunny location. It is not necessary to fertilize since the plant's useful life is two to four weeks. Most forced spring-flowering bulbs should be discarded after flowering.

Gardenias - The night temperature should be near 60°F and 70°F to 75°F during the day. Maintain high humidity around the plant and keep the soil uniformly moist. High temperature and low light intensity will result in flower bud drop. Some gardenia cultivars are hardy outdoors -- most florist gardenias are not hardy. Gardenias decline rapidly after flowering and should be discarded.

Geraniums - Potted geraniums are typically available March through June. Many new types are available, including vining and hanging basket cultivars. Bright light is essential to keep geraniums flowering. Geraniums respond favorably to having the soil dry out between waterings. Keep them in pots or transplant into the landscape once the danger of frost has passed. They are not winter hardy and must be brought indoors before frost if you wish to over winter them.

Gloxinias - need bright, indirect light; high humidity; and warm night temperatures (65°F to 70°F). Gloxinias need more light than African violets; place them in a bright window just beyond the reach of direct sun light. Keep the soil uniformly moist. Poor light, low humidity, and/or excessive soil drying can lead to the collapse of young flower buds.

Gloxinias need to rest before reflowering. When the leaves start to die back, gradually reduce watering until the leaves yellow and die. Place the pot in a cool, dark location and stop watering. Allow the tuberous stem to rest for a minimum of eight to ten weeks in dry soil. To stimulate reflower (although it's hard to do), resume watering when new growth appears and move the pot to a bright location.

Holiday cacti - prefer a relatively cool night temperature between 55°F and 60°F. Night temperature above 70°F inhibit flowering and cause bud drop. Place the plants in a well lighted location. Poor lighting leads to bud drop and poor growth after flowering. Water thoroughly, but allow to become moderately dry between waterings.

Holiday cacti bloom best when somewhat pot-bound. Repotting is necessary only about once every three years. Full sunlight is beneficial in mid-winter, but bright sunlight during summer months can result in pale to yellowish foliage. Holiday cacti require less water from October to March than when new growth is active (April to September).

Cacti will develop flower buds in the fall if the night temperature drops to 55°F. Where cool nights are not possible, cacti can be stimulated to flower by providing short days (11 hours or less of light each day) from mid-September to mid-October. This involves covering the plant with a light-tight box daily or moving to a dark location each night. Reduce watering and withhold fertilizer during flower bud development and flowering stages.

Hydrangeas - are generally recognized as outdoor flowering shrubs, but are also available as 6- and 8-inch pot plants in the spring. Flowers can last four to eight weeks if plants are bought as color first develops, watered adequately, exposed to mild temperatures (50°F to 60°F at night), and exposed to bright (but not direct) light. After the flowers fade, remove the flower heads and transplant into the landscape.

Kalanchoes - are available year-round in many colors. Flowers will last three to six weeks if plants are provided mild temperatures (60°F to 65°F at night) and medium light. Allow the soil to dry slightly between waterings; plants are easily damaged by over watering.

After flowering, cut off any tall growth and old flower stems. Keep the plants in a sunny location and move the plants outdoor after the danger of frost has passed. The best site is a bright, lightly shaded location. Kalanchoes will re-bloom if grown under artificial short days (long nights) for six to eight weeks. They can be grown successfully if kept in sunny windows or placed outdoors in late spring; they are not winter hardy.

Poinsettia - The colorful bracts of poinsettias may stay bright for months if cared for properly. If the plants are exposed to cold temperatures during transport home or placed near a draft the life of the "flowers" will be significantly shortened. Bright, indirect light (but not direct light) and frequent watering are essential. Do not allow the plant to wilt. Punch holes in the bottom of the decorative foil to provide drainage; poinsettias do not tolerate poor drainage. Temperatures between 65°F and 70°F are ideal.

Plants can be reflowered, although the procedure is somewhat demanding. Keep the plant indoors until the danger of frost has passed then move it outdoors. Remove the bracts when they wither and discolor. Keep the plant in high indirect light (morning sun/afternoon shade). Water and fertilize on a regular basis. Shape the plant as desired by pruning or pinching to encourage branching. Do not pinch after mid-August.

Bring the plant back indoors when night temperatures start to fall below 60°F. Continue to fertilize and water. Starting October 1, give the plant 14 hours of uninterrupted darkness daily until bract color is well developed (mid-November). This can be done by placing the plant in a closet or covering it with a cardboard box at night. Any light during the dark period will delay or inhibit flowering. Night temperatures should be between 60°F and 62°F. During the remaining 10 hours each day, provide maximum light with temperatures between 70°F and 75°F.

Orchids - are easily cared for if kept away from intense light and cold. They do very well under fluorescent lights or near a south facing window. Most orchids bloom only once a year, but the blooms can last as long as two months. Fertilize only when new leaves appear. Water often but allow the bark medium to dry out thoroughly between waterings. Orchids can be grown outdoors under the shade of trees after the danger of frost has passed.

Consumer Horticulture | Quick Reference

© Erv Evans, Consumer Horticulturalist
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