Paphiopedilum (Slipper Orchids)

Growing Paphiopedilum

Light
Paphiopedilums are low-light orchids. Most Slipper Orchids require shady conditions as in their natural forest floor habitats. Grow your Slipper Orchid in a shaded position in summer, protected from direct sunlight, and move it to a bright, unshaded position in winter. An east or west window or near a shaded south window are best.

Temperatures
Paphiopedilums are separated into 2 groups:
The warm-growing mottled-leaved types: should be kept at 60-65ºF (15-18ºC) during the night and 75-85ºF (23-29ºC) or more during the day.
The cool-growing green-leaved types: should be kept at 50-60ºF (10-15ºC) during the night and 75-80ºF (23-26ºC) during the day.
However, many growers raise the plants in the same temperature range with great success. Paphiopedilums can withstand night temperatures in the 40s (4ºC), as well as temperatures to 95ºF (35ºC).

Water
Because of the absence of any water-retaining pseudobulbs, Paphiopedilums need a moist medium – never soggy, but never dry. Water once or twice a week in spring and summer. Place your Slipper Orchid in the sink and allow lukewarm water to run through the pot for a minute or so. Drain the plant completely. Allow the compost to dry out a little between watering. Reduce watering during the winter months, but do not let the compost dry out completely. Avoid overwatering, and be careful to keep water out of the crown of the plant. Water can collect in the natural depression formed by the arching new leaf, and if coupled with low air circulation, it can cause this tender new growth to rot.

Humidity
Maintain high humidity (40-50%) for most of the year by standing container in a tray of damp pebbles. Do not mist the plant.

Fertilization
Fertilize once a week after watering. 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 is important to flush with clear water monthly to remove excess fertilizer, which can burn roots. In winter, fertilizer applications once a month are sufficient.

Potting
Repotting should be done yearly or every two years, or as the medium decomposes. Re-pot after flowering. Paphiopedilum orchids like to be tight in their pots. An average plant should have a 4-6 in. pot (10-15 cm). Be careful when repotting, as the roots can be brittle and are easily broken. Ensure the base of the new growth is in contact with the potting medium to ensure proper growth.

Propagation
After flowering, large plants can be divided by pulling or cutting the fans of the leaves apart into clumps of three to five growths.

Pests and diseases
Paphiopedilums are generally disease free. Keep an eye out for aphids, glasshouse red spider mites, and mealybugs.

Tips for reblooming

• Check regularly if the plant is secure in its pot and the root system is sound. If not, repot.
• Try applying a blooming fertilizer in the early spring months.
• Move the orchid to a cooler, brighter location for a week, then return it to its original location.