THE THANKSGIVING CACTUS
By Dr. Leonard Perry
Extension Greenhouse and Nursery Crops Specialist
University of Vermont
You have probably heard of the Christmas
cactus, which produces gorgeous red and pink blossoms
during the holiday season. But did you know that there
is also a Thanksgiving cactus, which, as you've probably
guessed, comes into bloom in November?
You can tell the Thanksgiving cactus (Schlumbergera
truncate) apart from the Christmas cactus (Schlumbergera
x Buckleyi) from the shape of its leaves. It has sharply
serrated or "toothed" leaves as compared to
the more rounded leaves of the Christmas cactus.
You may see the Thanksgiving cactus listed
as zygocactus in some books, its former Latin name.
And to confuse things even more, there's also an Easter
cactus (Rhipsalidopsis gaertneri) with leaves that are
almost three-dimensional with a thick ridge on one side.
This cactus blossoms in the early spring.
Most garden centers carry holiday cactus
plants although it is easy to grow them from cuttings.
When planted in a decorative pot, they make a nice hostess
gift, holiday table centerpiece, or present for friends
To propagate, snip off a branch with four
or five segments or sections of leaves. Dust the cut
end of the cutting with a fungicide or rooting powder
to help the new plant grow roots.You can buy rooting
hormone at your local garden center or nursery supply
store. It is usually a good idea to place the cutting
where it will get good air circulation, out of direct
sun, for a week or so to allow the wound to begin healing
Fill a small flower pot with potting soil,
vermiculite, or damp sand. To plant, push the root end
of the cutting into the potting medium about one inch
deep. The medium should be kept just barely moist, not
wet. To help prevent the soil from drying out, invert
a plastic bag over the pot. Use straws or popsicle sticks
to keep the bag from resting on the foliage. Vent frequently
to keep from being too moist.
For best results, place the pot in a spot
that gets plenty of light but is out of direct sunlight.
You should see new growth in three to four weeks.
Once your plant becomes established, allow
the soil to dry out during "resting periods,"
or in other words, when it is not producing blooms.
Water only when the soil is very dry to the touch. Overwatering
can kill the plant. Provide plenty of indirect light
and room temperatures of 60 to 65 degrees F.
Beginning in early to mid-September, these
cacti will need 12 to 14 hours of total darkness along
with cool nighttime temperatures in order to form buds.
The easiest way to achieve this is to place the plant
in a closet from 6 p.m. to 8 a.m. Or you can cover it
with a large brown paper bag. If you keep the plant
in a cool room (around 50 degrees F 24 hours a day)
in September and October, chances are excellent that
it will produce flowers, regardless of day length.
Once buds start to form, apply houseplant
fertilizer according to label directions to encourage
lush growth and an abundance of blooms. Too high a temperature
or too low a light level will cause buds to drop. Repot
as needed to prevent plants from becoming rootbound,
which will inhibit bloom. However, as these plants can
grow quite large over time, and will live for years
with proper care, you may want to keep them fairly pot
bound to keep them small.