Orchid Care - Paphiopedilum
The Slipper Orchid: Paphiopedilums are the Old World relatives of North American temperate- zone lady's-slipper orchids, the cypripediums. Perhaps no other orchid excites the same dedication as do these semiterrestrials. And, happily, 'paphs' are one of the best orchids for home growing, requiring only fairly bright light and normal home temperatures to provide some of the orchid kingdom's longest-lasting and most exotic blooms. There are classically several general types of paphiopedilums requiring slightly different cultural regimes, though all should do well with the general care instructions given here. Slipper orchids can last eight to 10 weeks or more in bloom.
Sufficient light is important for healthy growth and flower production. PROVIDE Bright light, no direct sun. In the home, an east, west or shaded south window. In a greenhouse, about 30 percent full sun. Under lights, four 40 watt fluorescent tubes and two 40 watt incandescent bulbs directly over plants. Foliage should be naturally semierect, and firm, not drooping. Dark green, limp foliage indicates too little light.
Mature plants need a 15 to 20 F difference between night and day.
Nights of 55 to 60 F; days of 70 to 85 F. Seedlings need temperatures five to 10 degrees higher than mature plants.
Mature plants should never dry out between waterings. Seedlings need even more constant attention to moisture.
Paphiopedilums need 60 to 70 percent. In the home, place on trays of moistened pebbles. In greenhouse, use a humidifier if conditions are too dry.
Must be provided on a regular basis because most potting media have little, although paphiopedilums will grow and flower with less fertilizer than will most orchids.
The exact fertilizer you use will depend on the mix in which your plant is growing. A good general rule is to use a balanced (10-10-10, 12-12- 12 or similar ratio) fertilizer 'weakly, weekly.' That is, fertilize every week at one quarter of the recommended dilution.
Should be done every one to two years before mix breaks down too far. Can be done almost any time of year, using a well-drained but water-retentive mix.