As we enter the holiday season, several ornamental houseplants are purchased for home and office. Among the most popular are Christmas cacti and the poinsettias. These can be excellent plants if properly cared for.
Christmas cactus is a popular winter-flowering houseplant native to Brazil, available in a wide variety of colors, including red, purple, oranges, pinks and creams. Its long stems make it a great choice for hanging baskets.
The plant prefers brightly lit areas of indirect sunlight. Do not place in areas of cold or hot drafts of air. The soil should be kept moist but not water-logged and the plant needs to be misted weekly to increase humidity. Do not fertilize when the plants are in flower, but do fertilize once a month between April and September. The short, cool days of the fall initiate the onset of buds for winter flowers.
The secret of good flower bud production involves temperature and dark (photoperiod) control. To initiate flowering, the plants must have a combination of bright light, night temperatures between 55 and 65 degrees, and the long nights - 13 hours or more of continuous darkness each day is required before flowering will occur.
Long nights should be started about the middle of September and continued for eight weeks. After the flowers drop off, pinch back to promote more branching. The plants can be placed outside in a shady or part shade location after all danger of frost is past.
Poinsettias are the most popular and well known of the holiday plants.
The brightly colored bracts, that come in red, white, pink and cream colored, are among the most beautiful. The actual flowers of the poinsettia plant are the small, yellow blooms in the center of the colorful bracts.
Consider the following tips in selecting poinsettias:
· plants with fully mature, thoroughly colored bracts, having an abundance of dark, rich green foliage all the way down the stem
· the leaves and bracts should not be drooping
· the plants need to be balanced, full and attractive from all sides, with stiff stems, good bract and leaf retention, and showing no signs of wilting, breaking or drooping.
The poinsettia needs to be in a bright location, receiving at least 6 hours of bright, indirect sunlight each day. Avoid direct sunlight, since it may fade the color of the bracts. The daytime temperature should not be any more than 70 degrees and needs to be kept away from drafts, excessive heat or dry air from appliances, fireplaces or ventilating ducts. Temperatures that drop below 50 degrees cause chilling injuries, leading to premature leaf drop. Poinsettias require moderately moist soil, not too dry or too wet. Water them thoroughly when the soil surface feels dry to the touch. Water until it seeps out of the drainage hole and the soil is completely saturated. Never fertilize a poinsettia when it is in bloom.
In the spring, when the colorful bracts fade, prune the back the plant to about 8 inches in height. The plant will look bare after pruning; eventually new growth will emerge from the nodes up and down the stem.
Keep the plant near a sunny window and continue to water it regularly during its growing period. You can take the plant outdoors once the night temperature remains above 50 degrees. Fertilize the plant every two to three weeks during the spring, summer and fall with a well-balanced complete fertilizer such as 10-10-10. Bring them back indoors when the temperatures drop below 50 degrees in the fall.
Long nights (short days) initiate the flowering of poinsettias.
Starting in late September, the plants need to have 13 hours of uninterrupted darkness. The exposure to any light source, car lights, room lights, etc., will delay or prevent flowering. Place them in a dark closet or in a box for 13 hours and then bring out to a sunny window.
Timothy Daly, MS, is the Agricultural and Natural Resource Agent with Gwinnett County Extension. He can be reached at 678-377-4010 or at firstname.lastname@example.org.