(First published in the InterTown Record in three parts in 2018)
As it is so often, research into a particular plant has my head
spinning. What I’d always assumed, is not necessarily true, and various
websites have slight differences in their explanations.
Schlumbergera bridgessii is the scientific name for Christmas cactus. The cultivars are also known
as Thanksgiving cactus, crab cactus and holiday cactus. Christmas cactus
is not really cactus but a succulent. Wikipedia says, “Nearly all cacti are
succulents, but not all succulents are cacti.” (Succulents are plants with
parts that are thick and fleshy which enable water retention in arid
conditions.)
One
site said the Christmas cactus does not naturally exist in nature. It was bred
from two other plants grown in the rainforests of Brazil. It has segmented,
flat stems of a glossy green which can hang down about 36 inches. Flowers form
on the ends. The bright blossoms are unique in that they may have several tiers
of petals making the entire flower up to 3 inches long. Each one can last
for several days, and the entire blooming period spans several weeks.
Because
the plant comes from rainforests it prefers humidity and requires more water
than what one would assume of a cactus. Homes around here can be very dry. A
little extra care in the winter may require putting the cactus in a pebble
tray. Place pebbles in the tray and add a little water. Don’t cover the
pebbles. Set the cactus pot in the tray but not so the plant itself is sitting
in the water. The evaporating moisture will help provide humidity. (I bought a
couple of cheap, pretty trays at Family Dollar and with colorful stones and/or
river rocks added, it makes a cute setting).
Basic
care of a Christmas cactus is keeping it out of drafts, watering when it feels
dry, providing adequate light and occasional feeding. One thing of interest,
though, is that Christmas cactus requires a certain amount of darkness.
I
think my Christmas cactus liked me writing about it last week. (Doesn’t most
everything like a little attention?) The plant has sprouted more and looks
vibrant. Oh OK, perhaps it’s because I’m giving it more water now that I
understand it’s not a real cactus.
Speaking
about watering, here are some tips. Water when the top inch of soil feels dry. Soak the soil until water runs through the pot’s drainage
holes. Give it a few minutes then discard any excess water in the drip pan. If
you use a pebble tray let the extra water in the tray evaporate to provide
humidity around the plant. Just make sure the plant isn’t sitting directly in
the water (which could cause brown spots, or root or stem rot). Pebble trays and the pebbles need periodic
cleaning.
A
mild household plant fertilizer is beneficial, too, about every other week.
However stop feeding a month before the plant will bloom, usually late summer
and fall.
I
learned two “thermo-” terms in this research regarding blooming and achieving
the best growth in plants. Thermo-periodic is the technical term used for the
amount of day light time the plant is exposed to in a 24-hour period. Thermoperiodism refers to the day and night temperature
fluctuation surrounding the plant.
Christmas
cactus likes indirect sunlight and does best in east or north-facing windows.
It can adapt to low light conditions but will bloom better in bright, indirect
light. Too much direct sunlight may burn the leaves. Ideal
day temperatures should be around 70 degrees and evening temperatures 60-65
degrees.
I
mentioned last week about the ability to choose when you want your cactus to
bloom. Of course most people want theirs to bloom around the fall/winter
holidays, although the plant can also bloom during the summer. If you want more
control, whatever date or holiday you choose, simply cut back watering and
hours of daylight six to eight weeks before you want it to bloom.
This
will force the plant to go into its dormancy/rest period. (Whether you are
trying to change its regular bloom time or not, it still needs a period of
dormancy.) It will also need more darkness; 12-14 hours of total darkness, meaning
no indoor light or neighbors’ lights. (I have neighbors who leave their outside
lights on all night.) Some people cover the plants or put them in a closet.
Dormancy temperature is best at 50-60 degrees. It the temperature is over that,
the plant will need 15 hours of darkness.
New buds will eventually begin to appear and, at that time,
increase the water times – but not the amount. Buds will fall off with too much
water or if the pot is moved around. Blooming time is usually four to six weeks
in bright, indirect light. The flowers can last up to
nine days.
Once flowering time is over, the plant can be trimmed back for
uniformity. Pinch off enough sections to achieve the shape you want. Normal
watering and fertilization can begin when new growth appears.
To continue about Christmas cactus care: Christmas
cactus prefers snug pots with its roots tightly confined in well-draining soil.
This snugness helps the root system produce better blooms. The plant will only
need to be repotted every two to three years.
Repotting is usually best done in spring or early summer when
the plant is not blossoming. This allows the plant time to acclimate before
blooming again.
Pruning helps keep the plant healthy, keeps it shaped and
confines the growth to the available space in the home. Pruning also encourages
the plant to branch out and start growing again. Give it about a month to rest
after the blooming period is complete, though. To prune, gently twist the stem
between the segments on the stem and remove the section. Up to 1/3 of the
Christmas cactus can be removed each year without causing damage to the plant.
Sections trimmed off can be placed in a new pot to create more plants. Bury the
last segment in potting soil.
Fertilize with a houseplant fertilizer April through October.
The plant can be moved outside to a shady spot in the summer until temperatures
drop below 50 degrees.
Two issues with these plants are stem rot and root rot.
Root rot can happen if the roots sit
in wet soil. The plant can be saved if the damaged root can be removed. However
if the rot has moved up the stem, stem rot,
a fungal problem, occurs. If this happens start a new plant before the
infection spreads too far.
My Christmas cactus had two more blossoms during the third week
of February.
