Sedirea japonica

Photographed by Colleen Pruett.

Culture of Sedirea japonica

LIGHT
Sedirea japonica prefers medium light levels, from 1500 - 2500 foot-candles. If you are growing under fluorescent lights, keep the plants about 6" - 8" from the tubes. Under high-intensity lamps, grow approximately 4 feet from the fixture. This plant can be grown on windowsills, given an east, south, or west exposure. Plants may be grown outdoors in the summer with filtered sunlight.

TEMPERATURE
This plant is an intermediate grower. In the spring and summer, day-time temperature should be 65º to 75º F during the day, with a 10º to 15º difference at night. During winter months, day temperatures can be below 60º F, night temperatures down to 50º F.

HUMIDITY
should be kept from 40 to 60%. Use humidity trays or a small room humidifier when growing on windowsills.

WATER & FERTILIZER
Use clean water, such as rainwater, distilled or reverse osmosis water if possible. Flush the plant regularly, especially if using municipal or well water. Never use artificially softened water. Let the plants dry out between watering. Use ample water in spring and summer while the plants are in active growth and in flower, reducing quantities during cooler winter days. Use a balanced fertilizer year-round, preferably urea-free. If using rain, distilled, or reverse osmosis water, add some municipal or well water to supply the necessary calcium and magnesium. Fertilize very lightly every other watering during the growing season, once a month during the winter should do.

FLOWERING
Sedirea blooms primarily from spring through early summer. The inflorescence may have from three to twelve flowers. The flowers are cream to green, with magenta spots on the lips. They will last from one to two months, and are fragrant both day and night.

Flower with heavier striping

REPOTTING
Repotting of this plant is preferably done in the spring and early summer, every two to three years, just after blooming. Either clay, plastic, or net pots, or wood baskets will work.

Sphagnum
Using a good-quality, long-fibered sphagnum moss, place the root ball over a small amount of moss. Wrap the root ball securely in sphagnum moss, so that the plant does not wobble. Don't wrap too tightly, or the water will tend to run off. Keep the base of the plant a little higher than the rim of the pot. Plants can be similarly planted using osmunda fiber.

Possible Potting Mixes
A: 3 parts sphagnum, 1 part perlite or #3 sponge rok, 1 part medium tree fern fiber
B: 3 parts fine fir bark, 1 part perlite or #3 sponge rok, 1 part fine tree fern fiber
C: 3 parts fine fir bark, 1 part perlite or #3 sponge rok, 1 part chopped sphagnum
Any of the above mixes can be used - or something similar - these plants are not very particular. You want to have an open mix that will drain freely. Pot as you would most other orchids, keeping the base of the plant above the top of the media.

When growing in a basket, line the basket with a thin layer of sphagnum or coconut fiber to keep the mix from falling through the slats.

Plants may also be mounted on cork or tree fern plaques, or on wood branches like oak, sassafras, etc. You can mount the plants with a little sphagnum or osmunda to help keep them moist.