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Stubborn Bloomers

Flowering houseplants can be a real joy and source of pride…if they flower! Stubborn bloomers can be very frustrating. Here are some tips on getting flowering houseplants to do their thing.
African Violets: Probably the most popular flowering houseplant, violets bloom best in bright light (an east-facing window works very well.) If you do not have a bright window, you can supplement with artificial light, even if you just set the pot under a table lamp that is on for a few hours. Other requirements are proper watering (no over- or under-watering stress), the right pot size (too large a pot will delay flowering), and regular fertilizing. A healthy violet that is in the right light situation should flower fairly regularly.
Amaryllis: Sub-tropical bulbs, amaryllis are usually forced into flower for Christmas, following a fall dormant period. When flowers fade, remove the flower stalk, but keep the leaves so that the bulb can store the needed energy for its next blooming season. After a spring and summer of bright light with regular watering and fertilizing, allow the foliage to die back, and store the bulb dry in a cool, dark location. This dormancy needs to last eight to ten weeks, after which the bulb can be placed into new medium, watered, and brought back into a bright location. The flowers appear first, followed by long strap-like leaves. 
Christmas Cactus: These popular plants are “short-day” bloomers. They initiate flower buds during the winter with long cool nights, and then flower in the spring, which for us, with the help of a little seasonal trickery, is Christmas! Growers (and you can also do this) trick these plants into thinking that fall is winter. They use black-out cloth to control the length of the day and keep the temperatures on the cool side. At home, leaving the plant outside until danger of frost will supply the cool night temperatures needed for bud initiation. This usually does the trick, but if you still do not get blooms, try controlling the day-length as well. This can be managed as simply as placing a large box over the plant at the end of an eight or nine hour day. Fertilize your plant over the spring and summer, but stop fertilizing at the end of the summer.
Hoya: Mostly vining plants grown primarily for their foliage, but which produce wonderful clusters of waxy flowers. Like many flowering plants, hoya like to be somewhat pot bound to do their best blooming. Flowers reform on old flower stalks (“spurs”), so pruning may retard flowering, as new growth is slow to produce flowers. Either direct morning sun or late afternoon sun will also help with flowering. The natural bloom time for these plants is summer. Soil should dry slightly in warm seasons, but keep these plants drier in winter.
Jasmine: The tropical Sambac jasmine (or Arabian Jasmine) blooms best in direct morning or late afternoon sun, but will also take full sun outside in summer. The Sambac is a shrubby vine that should be pruned after flowering. Fertilize regularly and enjoy small fragrant flowers intermittently all year, although flowering should slow in winter. Pink jasmine (J. polyanthum) is a late winter/early spring bloomer, with fragrant white flowers from pink buds. Protect from mid-day sun in winter, but it will take full sun outside in summer. Prune after flowering and as needed in summer. Stephanotis (Madagascar Jasmine) is a woody vine that blooms in summer, and benefits from a winter rest period (less water, less fertilizer, cooler nights.) Prune this plant in early spring.
Kalanchoe: This flowering succulent is popular for its long-lasting clusters of small waxy flowers in a variety of colors. The thick, wavy-edged leaves indicate that the soil should dry moderately between waterings, although less dry while in flower. This is a short-day bloomer, budding up after the winter. As with many short-day plants, you can trick it into flower by giving it a cool, shorter day for several weeks. After flowering, remove old flower stalks, give it very bright light, and fertilize during warm months. Like most succulents, do not over-pot.
Orchids: The many different species and hybrid orchids that make good houseplants all have specific needs; but in general, failure to flower can usually be blamed on incorrect light levels, insufficient fertilizing, or the absence of a drop in temperature from day to night. If the plant looks healthy but does not re-bloom within a year, you should adjust one or more of these factors, based on which orchid you have. Too much or too little light can often be diagnosed by the leaf color, as can lack of fertilizer. Bring your orchid in and we will be happy to look at your plant and advise you on what we think is the problem.
Peace Lily: The problem with these reliable plants is usually one of watering, where too much or too little water causes yellowing or browning leaves that take away from the plant’s natural beauty. However, we do find that sometimes they just won’t go back into bloom. Some varieties of Peace Lily (Spathiphyllum) are seasonal bloomers, where they do a big flush of bloom once or twice a year. Others have been cultivated to flower intermittently throughout the year. In general, Spathiphyllum bloom best in bright indirect light and higher humidity. They also require regular fertilizing during warm months. As with most flowering plants, over-potting may cause delay in flowering, so pot up gradually only as needed.
If you have any another flowering plant that just won’t bloom for you, check with us or seek information on-line about its natural flowering cycle.
P.S.: Wouldn’t ya know…when you do not want them to, there are some houseplants that will flower. For example, Chinese Evergreen (Aglaonema) produces a sort of closed version of its relative the Peace Lily’s flower. These should be removed when you see them, so that the plant will put its energy into more attractive foliage instead of these very mediocre blooms. The Corn Plant (Dracaena fragrans massangeana) and other Dracaena will occasionally put out a tall, unattractive flower stalk that causes a temporary discoloration of the newer leaves, as well as dripping sticky nectar from the flowers onto leaves or floor. These Dracaena flowers are fragrant, but show no other redeeming feature. Snip it off before the flowers open!
Posted: 6/29/2013 by Margot | with 0 comment(s)
Filed under: MargotGunn, TheGreatIndoors
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