Terrestrial Orchids
Most orchids are epiphytes that grow on trees. Terrestrial orchids, or ground orchids, obviously need somewhat different care! The main differences have to do with the type of potting mix used. Most orchids from temperate regions are terrestrial, but there are plenty from tropical areas too. Different orchid types have different climate considerations, such as light, water, and temperatures, so I won't address those here. Most ground orchids still don't grow in dirt! Bogs, leaf litter, and clumps of moss are more common. So they should still have a freely draining, airy potting mix. But it should have considerably smaller particles than you'd use for epiphytes. A mixture of equal parts sand, sphagnum moss, and gravel or fine-grade fir bark is a good starting point. Some plants like to be kept moist, while others come from drier climates; adjust the water-retentiveness of the potting mix accordingly. For example, Cypripediums come from bogs, and can tolerate a somewhat denser mix, so recommend equal parts sand and peat. (There are more instructions on the Cypripedium page.) Some of these plants don't like their roots disturbed. For these, use potting mixes that last a number of years before they break down! Inorganic components, such as sand, gravel, perlite, and lava rock last practically forever. Peat also lasts well, because it has preservative properties: long-dead people are sometimes discovered sunk in peat bogs, undecayed! As with all orchids, the key to growing these is to reproduce their natural habitats. Mimic the sorts of materials they'd be growing in naturally, and they'll do well.What Potting Mixes do YOU use for Terrestrial Orchids?
There are lots of possible recipes for terrestrial orchid potting mixes. What works well for you? I'd like to hear about it, and so would other readers! Does it work better for some types of orchids than others?