lady's-slipper orchids, originate in the jungles
of the Far East including Indonesia. They are
semiterrestrial, growing in humus and other
material on the forest floor, on cliffs in
pockets of humus and occasionally in trees. They
are easy to grow in the home, under lights or in
L I G H T is
easier to provide for paphiopedilums than many
other types of orchids. They require shady
conditions, as in the home in an east or west
window, or near a shaded south window. In the
greenhouse, shade must be provided. Give about
1,000 to 1,500 foot-candles. In the home,
fluorescent lighting is excellent; suspend two or
four tubes 6 to 12 inches above the leaves.
T E M P E R AT U R E S
for paphiopedilums cover a considerable range.
Paphiopedilums are traditionally separated into
two groups: the warm-growing mottled-leaved types
and the cool-growing green-leaved types. A third,
increasingly popular group is the warmer-growing
strap-leaved multi-floral paphiopedilums.
Warm-growing types should be kept at 60 to 65 F
during the night, and 75 to 85 F or more during
the day. Cool-growing types should be kept at 50
to 60 F during the night and 75 to 80 F during
the day. However, many growers raise all plants
in the same temperature range with excellent
results. The plants can stand night temperatures
in the 40s if necessary (as when grown outside in
mild climates), as well as temperatures to 95 F.
Care must be taken to protect the plants from rot
when cold (keep humidity low, and avoid moisture
on leaves or in the crowns of the plants), and
also to protect from burning when hot (shade more
heavily and increase humidity and air movement
around the plants).
W A T E R must
be available at the roots constantly, because all
plants in this genus have no pseudobulbs. All of
these plants need a moist medium -- never soggy,
but never dry. Water once or twice a week.
H U M I D I T Y
for paphiopedilums should be moderate, between 40
and 50 percent, which can be maintained in the
home by setting the plants on trays of gravel,
partially filled with water, so that the plants
never sit in water. In a greenhouse, average
humidity is sufficient. Using an evaporative
cooling system in warm climates can increase the
humidity. Air movement is essential, especially
when humidity is high.
F E R T I L I Z E
on a regular schedule, but care must be taken to
avoid burning of the fleshy, hairy roots.
High-nitrogen fertilizers (such as 30-10-10) are
recommended when potted in any fir-bark mix. In
warm weather, some growers use half-strength
applications every two weeks; others use
one-quarter strength at every watering. It's
important to flush with clear water monthly to
leach excess fertilizer, which can burn roots. In
cool weather, fertilizer applications once a
month are sufficient.
P O T T I N G
should be done about every two years, or as the
medium decomposes. Seedlings and smaller plants
are often repotted annually. Mixes vary
tremendously; most are fine- or medium-grade fir
bark, with varying additives, such as perlite
(sponge rock), coarse sand and sphagnum moss.
Moisture retention with excellent drainage is
needed. Large plants can be divided by pulling or
cutting the fans of the leaves apart, into clumps
of three to five growths. Smaller divisions will
grow, but may not flower. Spread the roots over a
small amount of medium in the bottom of the pot
and fill with medium, so that the junction of
roots and stem is buried ~/2 inch deep in the
center of the pot. Do not overpot; an average
plant should have a 4- to 6-inch pot.
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