The orchids sold most often, such as moth orchids (Phalaenopsis), Cattleya, Dendrobium and Oncidium, are epiphytes. In nature they cling to tree bark, with their roots in open air, catching rain and the bits of debris that gather in crevices. That is why they are not grown in ordinary potting soil.
Instead, they go in chunky media such as fir or pine bark, sphagnum moss, or mixes of bark with charcoal and perlite. Bark dries faster; sphagnum holds more water. The American Orchid Society puts it well: you can change the medium more easily than your habits. If you tend to water often, choose a coarser mix; if you forget, a moister one.
Water thoroughly, letting water run through the pot for a while so salts are flushed out, then let it drain completely. Water again as soon as the medium has nearly dried, checking with a finger rather than a schedule. Orchid roots do not tolerate sitting in water or media that stays soggy.
Light is the usual reason orchids fail to bloom. The Society suggests most orchids indoors take as much light as they can without burning, often one to four hours of direct sun.
Key points
- Popular orchids are epiphytes and grow in bark or moss, not soil.
- Water thoroughly, drain well, and water again as the medium dries.
- Too little light is the commonest reason for no flowers.
Try this
Push a finger into your orchid's medium today. Decide from how it feels, not from the date, whether it needs water.
Check yourself
Read more in the reference
Sources
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