| Since not all accept the
name Tolumnia, and all hybrids are labelled oncidium, we will refer to them as
equitants.
This genera related to
the oncidiums, or still in it, is from the Caribbean islands. In their native
habitat, they are warm growers, with high humidity for most species. The amount
of water depends on which island and which area is their point of origin. T.
guianense is from a very arid area of the island of Hispaniola, mainly on the
Haitian side where they get most of their moisture from dew. Others are from
beachside in the Bahama Islands and are subjected to nearly daily rainfall and
nightly dew.
The general conditions
for good culture are high light, high temp, high humidity, and water. Since
many equitants die from improper watering, to me water is the most important
factor in proper culture. The first thing to consider is your media, and that
will tell you how often to water. I have seen/used all of the following media:
loose charcoal, loose treefern fiber, treefern plaques, cork plaques, and even
sphagnum moss ( though I would not recommend it). Each method requires a
different watering frequency.
WATER:
This is the first
consideration when growing equitants well. Once you figure out how often you
are going to water the equitants, then you can choose the potting media. Since
equitants dont have a pseudobulb or other water retaining biological
mechanism, they want to have moisture when they need it and want to be dry the
rest of the time. We need to supply this need either by having a minimally
retentive media or a non-retentive media and adjusting our watering to match
the media. OR, do like I do and match the media to my watering
schedule.
Equitants want to get
their roots wet so they can get the moisture they need, and then they want to
dry out so they are not waterlogged. I killed my first cork mounted equitants
because I didnt give them enough water, I watered at the frequency of the
ones I have potted. They didnt appreciate it very much, and expressed it
by turning brown.
Potted plants or plants
in a water retentive media will need to be watered every two or three days, 2-3
times a week. Plants mounted on cork will need to be watered every day or every
other day, but misted more often.
POTTING AND
MEDIA:
Potting is the second
consideration I use, after choosing how often to water. Match the two methods,
and your equitants should do well.
I grow my equitants
mainly in clay pots, with loose long tree fern fiber tightly packed into the
pot. If a plant has a poor root system during repotting, I will wrap the roots
that are present with one or two long sphagnum fibers. Since the water/dry
cycle will break down the sphagnum moss and make it less water retentive. So
after a couple of weeks, water retention is no longer a problem, at about the
same time new roots have formed. Cool timing, the way the two go together. In
this method, I water 3 times a week in summer, and twice a week in winter in
Miami Florida.
My second most common
method is to pot the plant in a pot using medium charcoal chunks. Again, it is
a method which will retain moisture for a short time, but then dries quickly.
Although some people say that the charcoal will filter out the impurities of
the water, I believe that after a few weeks/months, it absorbs (adsorbs) all
the stuff it can handle and is then no more effective than any other media. My
beliefs only, no other claims are claimed. But it has good qualities otherwise,
so who cares. I do like it better than aliflor, although a mix of the two works
well. I water 2-3 times a week with this method also. Another popular method is
tree fern plaques, hanging with the fibers oriented vertically. This method
allows the roots to explore throughout the plaque, and offers water retention
with quick drying. I tie a small thin pad of sphagnum moss on the plaque, and
then put the plant on the pad. Again, the water retention is not a problem
after a few weeks, but allows the plant to have more moisture retention when it
is establishing itself. I water these 2-3 times a week also.
Another popular method
is to mount the plant on cork. Again, use a small pad of sphagnum moss, and
mount the plant to the pad. The best pieces of cork for equitants will have
either folds or holes in them, so that the plant's roots will have a place to
suck up moisture while the cork is drying. A related method is to use a
roughcut cypress board, especially the kind used for outdoor fencing, instead
of the cork. Both cork and cypress require daily moisture, a spray or two from
a squirt bottle once or twice a day to simulate dew, and a full watering at
least once a week or so. I dont like this method since I dont want
to water every day. A method which does work, but I dont recommend is
sphagnum moss either in a basket or in a pot. You have to watch the watering
frequency with this method, and see if the plant is happy and adjust
accordingly. If you are experienced this will work, but is not good for those
who can't tell if the plant is unhappy from too much water or too little
water.
LIGHT:
Light is easy. Give them
as much as you can. When I first buy a plant, I dont know at what level
it was previously grown, so I start at low cattleya light and move it brighter
over a week or two. They need it bright to bloom. If the leaves start to turn
red, cut back slightly on the light, but maintain a high level, at least
cattleya light. They can do well indoors on a windowsill, or under metal
lights, but I had problems blooming them under flourescents indoors. They grew
well, but no blooms although I only had a two light setup, so it wasnt
that bright.
TEMPERATURE:
Since these plants
originated in the Caribbean, they like warm temps. They dont like to go
below the 70F range. They like it in the 90's by day, with the 80's by night.
They will tolerate temps in the 80's by day, with nights in the 70's, IF you
can keep the light bright they will still bloom. So windowsill is no problem
with the temps.
PESTS:
The most common pest to
attack equitants is scale. You have to be very determined to get rid of scale,
since the larva and eggs can get down in between the leaves and are hard to
reach. . I separate the plant, and its closest neighbors, so that the
infestation doesnt spread further.
The first line of
defense when you first see a scale is to use an alcohol based mix to kill the
little blighters and rub them off with a brush. I use a 50/50 mix of
water/alcohol with a few drops of soap, and scrub with an old natural bristle
1/2" paintbrush. I have cut off the bristles at about 1/2 inch, so there is not
much play while it is not too stiff. I like this better than a toothbrush.
After I am done, I set the pot in a bath of the mix, and let the pot soak for
10-15 minutes. Then I repeat at 4-7 day intervals for a couple weeks. If this
doesnt get rid of the scale, I move up to a chemical mix, preferably a
systemic insecticide. With a systemic, I dont need to contact the
insecticide by scrubbing with the brush. Repeat at 7 day intervals for a couple
of weeks. Use the concentration recommended on the label, a weaker solution
just breeds resistant bugs. Also, change insecticides every so often, so that
resistant bugs are not breeding.
Another problem with
equitants is that weak plants are susceptible to bacterial infections. I use
rd20 or phyton27 when it happens. You can tell when they are infected because
the fans turn yellow and fall off.
CONCLUSION:
The two main variables
are watering frequency and potting media. Light and temp are constant for all
the equitants, high levels of each. If you follow the matching method I
outlined above, you should have no problem with culture. = |