Gardening in December
December in New Hampshire is, as it is everywhere, a festive season.
It is a time when people scurry about doing shopping, decorating and entertaining;
therefore the last thing on their minds is yard and garden work. This
is the perfect time to focus on indoor plants and to purchase some Christmas
Cactus, Kalanchoes, Cyclamens, or Poinsettias to make your home more festive
or to share these seasonal potted plants with others.
The Christmas Cactus is a staple plant for the holidays. This popular, winter flowering houseplant is available in a wide range of colors including salmon, deep rose, red and white. The secret to good flower bud production involves control of the temperature and the amount of exposure to darkness. The ideal growing temperatures for this plant are 70 ° F during the daytime and between 60 and 65 ° F during extended dark hours (13 hours or more). While in bloom the Christmas Cactus requires bright, indirect sunlight and a reduction in water.
Kalanchoes are another popular seasonal plant. These succulents produce small, star shaped colorful clusters of flowers. Traditionally, these plants have either red or pink flowers but sometimes can be found with coral or yellow blooms. With their thick, succulent leaves for water storage, kalanchoe don't need a lot of water. Kalanchoes are excellent easy to care for plants for those non-green thumb individuals. They need bright indirect light (at least 4 hours a day) coupled with warm temperatures.
At night they prefer a cooler location so if your conditions are too warm you need to find a cooler location for them at night. They are one of the longest flowering houseplants and will provide you with months of pleasure if treated properly.
Cyclamen is another popular wintertime gift and holiday plant. Cyclamen is an unusual plant with dark green, heart-shaped foliage and butterfly-like flowers in colors ranging from white to light pink, lavender, hot pink, and hot purple. Most will bloom from mid-November until mid February, provided conditions are satisfactory. They prefer bright, indirect light and grow best when temperatures can be kept cool.
Ideal daytime temperatures for cyclamen are 60 to 65 degrees F with night temperatures around 50 degrees F. High indoor humidity is crucial, so to maintain a desirable level, fill a large plate, shallow pan or tray with water. Then set the cyclamen on an inverted dish, just out of the water.
Next to the Christmas tree itself, the poinsettia is the plant most identified with the holiday season. Poinsettias are tropical plants native to Central America and like warm temperatures and relatively high humidity. They are somewhat temperamental when they are grown in New Hampshire homes so be sure to treat them with care.
During the Holiday season (December -January) place these plants in a bright sunny east- facing window. If you live in an older house take care not to place the plants close to drafty windows. Also, be careful of heating registers and fireplaces because, if the temperature around the plant rises above 70-72° F, the flower bracts will start to fade. Otherwise, at this time of the year, the plant requires very little care.
When flower bracts start showing signs of fading (February -March), it is time to put the plant into dormancy. To start this process, heavily prune the plant back to about eight inches tall, leaving one or two leaves per branch. After pruning, cut back the amount of water so that the top inch (2cm.) of soil is dry between waterings. Do not fertilize the plant at all during this time.
In Mid-April increase the frequency of watering and fertilize with a 12-12-12 or 20-20-20 product. By late May the plant should be growing vigorously. This is a good time to re-pot if needed. In June it should be warm enough to put the plant outside, but be careful to shelter it from drying winds and keep a close eye on its soil moisture.
In summer (July-September) keep it well watered and fertilize about every other watering. Pinch back the branches about 2-3" to promote short dense growth and to prevent a leggy spindly look to the plant. By the end of September start preparing for the upcoming holiday season.
The poinsettia plant is photoperiod sensitive (like that of the Christmas Cactus) which means the plant is triggered to flower by the decrease in the amount of light it receives. Sensing that the days are shorter, the plants puts all its energy into reproduction (flowers and stamen). The poinsettia will set flower buds only after being exposed to short days (10 hours of light or less) for about 10 weeks.
This can be very tricky because the light cycle has to be very strict. Exposure to a 60-watt light bulb for ten minutes is enough to disturb the flowering cycle. An unused closet or large box is ideal for isolating a plant overnight. Each morning bring out the plant and place it in a sunny window where it will stay close to 70 ° F.
During autumn (October-November) make sure that the plant is not too cold during the night. Temperature should be between 45-55 ° F. After 9-10 weeks (mid-late November), the bracts should start to develop, and at this point, you are ready to bring the plant out to the normal household light.
All of these holiday plants are fairly easy to care for. Even the novice gardener can have success at decorating their home with lovely plants at this time of year. These plants can be found in florist shops, garden centers and nurseries. They can be purchased already in bloom or ready to grow and bloom for the holidays. In either case, be sure to read the care tag that comes with the plants and then sit back and enjoy a beautifully decorated home.
Call the UNH Cooperative Extension's Family, Home & Garden Education Center 's Info-Line toll-free at 1-877-3984769 for "Practical Solutions to Everyday Questions." Trained volunteers are available to answer your questions Monday through Friday from 9 am to 2 pm .
By Rachel Maccini, Coordinator Family, Home & Garden Education Center University of New Hampshire Cooperative Extension, Hillsborough County