Orchids are available in thousands of commercial species and varieties, according to the University of Florida. Most orchids require similar conditions as well as care. Although this holds true for most varieties, it is important to know your particular orchid's requirements. General care for orchids is usually quite similar for watering practices.
Few orchids live in potting soil, says Kent Kobayashi of the University of Hawaii. Most orchids require their roots to dry partially between watering to prevent root rot, which regular gardening soil does not permit. Wood chips, sphagnum moss, coconut fiber and peat moss are all desirable potting materials. Potting medium size determines how much water is retained. If the orchid variety requires only a small amount of watering, a larger medium is the better choice.
Orchids grown in potting media such as tree fern, osmunda, peat, charcoal or stone require a complete fertilizer with a 1-1-1 ratio, says the University of Florida. Orchids grown in wood chips are more prone to wood-decaying microorganisms and need more nitrogen, or a fertilizer with a ratio of 3-1-1, to survive. Water-soluble fertilizers are best applied once a month.
Watering depends on many factors. Each orchid variety has its own watering needs and should not receive more than is required. Orchids, as a general rule, require less watering when they are not actively growing during the winter months, says Kobayashi, and more during the spring and summer when actively growing. Orchids with thinner foliage usually require more watering than those with fleshy leaves. Most orchids like the potting material to dry out between watering. Flowering orchids require more watering. Water during the morning or midday.
Light and Temperature
Orchid leaf color is the best indication of whether the plant is receiving enough light. Orchids with light to medium green leaves and new leaves with a slight sheen are receiving the proper amount of sunlight. Too much light causes the green to leach from the leaves. Charred or curling leaves and flowers also indicate too much sunlight. Orchids do well in a lot of different temperatures, depending on the variety, but most orchids do well in temperatures between 50 and 90 degrees F, says Kobayashi.
Humidity and Air Circulation
Most orchids require as much humidity, between 40 and 60 percent, as other plants. Mist the leaves in the early morning if they seem to droop from lack of moisture. Orchids need good air circulation, so a fan to move the air will greatly improve the orchid's conditions.