| By
Dotty Woodson, County Extension Agent-Horticulture
Tarrant County
401 East Eighth Street, Fort Worth, TX 76102
GROWING
PHALAENOPSIS
Phalaenopsis
are very popular. The reason for their popularity is the flowers
last three months or longer on a graceful arching spike with many
flowers. Phalaenopsis flower in late winter and spring. Phalaenopsis
are easy to grow in normal home conditions if extra humidity is
provided. You can grow these wonderful flowers. Remember the basics
of horticulture is the same all plants, even orchids. If you can
grow plants, you can grow orchids.
Compare our
landscapes. Some of us grow impatiens in shady landscapes and some
of us grow lantana in sunny landscapes. We select the plants that
grow in the conditions that exist in our landscape. Use these same
principles for growing orchids. If you have a sunny growing area,
grow orchids that require a sunny location such as Oncidiums, Dendrobiums
and Cattleyas. If your growing area has low light, grow Phalaenopsis
and Paphiopedilums.
Light
Phalaenopsis
grow in low light conditions. Their exact requirement is 1,000 to
1,500 foot candles of light. Measure the light with a light meter
or judge if the light is coorect by the growth of the plant. Place
Phalaenopsis in an east or south window. The foliage will appear
yellow-green not dark green if the light is correct. Dark green
leaves or the new leaf growing longer and more narrow than the old
leaf indicates the light is too low. Phalaenopsis will grow under
artificial light. Grow Phalaenopsis 9 to 12 inches under fluorescent
grow lights or 4 to 6 feet under 400 watt High Intensity Discharge
lights or high pressure sodium lights. If your Phalaenopsis does
not have a flower spike growing by February, move it where it will
receive more light. Even a small incandescent light can make a difference.
Temperature
Phalaenopsis
grow well with normal household temperatures. The temperature range
for Phalaenopsis is 60° F to 85° F. The normal home temperature
of 72° F to 78° is fine for Phalaenopsis. Allowing the temperature
to drop below 60° F will endanger the plant. Check the temperature
at the window sill during the winter. In the fall, allow the night
temperature to drop down to 60° F for three weeks. This temperature
drop in combination with the short day length will induce the flower
spike. The flower spike should start to grow about three weeks after
the cold treatment.
The flower spike
will grow in the direction of the source of greatest light. The
flower placement on the spike, the arching spike and the symmetry
of the flowers is very important for the beauty of the flowers.
All the flowers will face the source of greatest light. Once the
flower spike starts growing, the plant should always face the same
direction (toward the window or artificial light). When you move
the plant to water it, place the plant back facing the original
direction. If growing at a window sill and the flower spike grows
into the window, do not turn the plant around. Move the plant way
from the window keep the orintation the same. If you turn the plant
around, the spike will continue to grow toward the window and you
will end up with a crooked spike. Move the plant only after all
the buds form and the first flower opens.
Humidity
Phalaenopsis
like most epiphytic orchids grow best with the humidity 50% or higher.
Most homes have a humidity of 30 to 40%. To create high humidity
around the orchid, provide a way for water to constantly evaporate
around the plants. Place gravel in a pan or saucer. Place the plant
on the gravel. Keep water in the pan or saucer about to the top
of the gravel. Do not allow the water to touch the bottom of the
pot. This growing method will create a micro-environment of high
humidity right around the plant. Pans to fit window sills or tables
can be custom ordered from sheet metal companies. Misting does not
substitute for humidity. Humidity is in the air. Misting is not
the same. Misting causes leaf spot diseases if there is not good
air circulation. Do not mist. Groupintg plants together what create
humidity because plant transpire water as a by-product of photosynthesis.
Watering
Water when the
orchid needs water. How often to water is influenced by humidity,
potting media, type of pot (clay or plastic), size of pot, time
of year and the orchid. Over watering is the biggest killer of orchids.
So when in doubt, do not water.
Orchids require
a thorough soaking. Do not just give them sips. Phalaenopsis are
epiphytic plants. The roots on epiphytic orchids are covered with
a spongy tissue called velamen. In nature, this tissue absorbs water
and nutrients from the air. In cultivation, the orchid roots have
this same function. Orchids require more air than terrestrial plants
around their roots. Look at the velamen on the roots. The tip should
be shiny green or red. The velamen should be plump and shiny gray
or silver. As you water, watch the velamen turn greenish. This color
change is a good indication that you are watering thoroughly. When
the velamen turns back to gray or silver, wait a couple of days
and water. If the orchid is potted in a peat based media, stick
a pencil into the media as you would stick a toothpick into a cake.
If the pencil comes out of the media with peat on it or with the
wood wet, do not water. Over watering turns the velamen brown and
mushy and the roots lose their ability to absorb water.
Potting Media
It does not
matter what media you use to grow orchids, but how you manage the
orchids in the media. Remember, the roots need air. Over watering
is the worst problem. The water displaces the air in the media.
Use a media with large particles so there is plenty of space for
air. Every orchid grower has their favorite media and are constantly
trying new ones. Find one that works for you and stick with it.
Peat based media are becoming popular because of the availability.
These media all have different formulas. Many of them have a wetting
agent which keeps the soil wet for a longer period of time.
Repot Phalaenopsis
in the late spring or summer after it completes flowering. Wash
all the old media off the roots. Using sterilized pruning shears,
cut off any damage or diseased root (brown and/or mushy). Healthy
roots are white and turgid. Pot the plant back in the same pot or
a bigger pot depending on the size of the roots. Pot to fit the
roots.
Fertilizing
Fertilize every
two weeks with a half strength fertilizer. Use a 3:1:1 ratio fertilizer
if the orchid is potted in bark media. Fertilize with a balance
ratio 1:1:1 if potted in a peat based media. Orchids, like other
plants, slow their growth down in the winter. Reduce the ampunt
of fertilizer during the winter. Fertilize Phalaenopsis with a 1:3:1
(high phosphorus) ratio fertilizer in November when the plants are
setting their flower buds.
After Blooms
Fade and Drop Off
Once the flowers
fall off the stem, cut off the flower stem above one of the lower
nodes. If the cut back stem remains green, some Phalaenopsis will
flower from the stem the current season or the next season. If the
stem turns brown, cut it off to the base of the plant.
Back to top of page |