The orchids commonly described as Jewel Orchids are usually found in the Subfamily Spiranthoideae, Subtribe Goodyerinae with about 35 genera and about 480 species.
They have patterned leaves that may have substantial color and generally small flowers.
Jewel orchids grow on the forest floor, in low light, along creeks and rivers in the loam and mosses, hidden among fallen leaves, where the leaf netting resembles the veins of the fallen leaves, hiding them.
Some can be found on mossy cliffs and rocky out cropping; these are regarded as lithophytes.
They tend to enjoy mildly acidic soils, regardless of limestone substrates.
They are generally creeping plants with few roots that arise at the nodes of a horizontal stem.
Most are genetically related, as interbreeding shows. They are also very old group of plants as indicated by the genetic diversity and the world wide range of these orchids.
Light Low light 500 to 1500 foot candles (easy to read a newpaper under), like Phalaenopsis.
Temperature Most like temperatures in the 60F to 90F (15C to 30C) range, though the Goodyeras can tolerate temperatures down to 30F (-1 C).
The following guidelines are for the temperature zones. However as most Jewel orchids grow in the mountains, in forests, and in warm regions; the temperatures are not so clear cut. Fog may be a daily event cooling everything down and humidity makes heat more bearable.
Temperate Zone - 32F to 45F (0C to 10C) in winter and 65F to 85F (20C to 30C) in summer, night and day temperatures respectively.
Subtropical Zone - 50F to 70F (10C to 20C) in winter and 65F to 90F (20C to 30C) in summer, night and day temperatures respectively.
Tropical Zone - 60F to 80F (15C to 25C) in winter and 90F to 96F (30C to 35C) in summer, night and day temperatures respectively.
Humidity below 50% is low, 70%+ is better. They do very well in terrariums with some air flow.
High humidity is the key to growing these plants along with dryish roots.
Water Recall the old adage: "Know how to water an orchid, know how to grow it". Water once a week from March to September, and half that during the resting season from October to February. Don't be shy about letting it really dry out to the point of wilting. Root rot can kill a hard to find plant.
Media Jewels like an acidic medium, pH of 5.5 to 6. A mix of 10% charcoal, 50% houseplant soil, 40% 1/4 in (3mm) bark is a good mix. Repot infrequently. Use shallow pots, less then 2 in (5 cm) deep. Repot in spring when new growth appears. If the roots rot off, cut off the rot, dry for 2 days, then repot. You may find sphagnum is fine during the growing season but too wet in the dry season.
Pests Not a lot of bugs eat Jewel orchids.
Mites - are very small spider like pest that can damage plants very quickly making the leaves look sandblasted.
Low humidity brings mites.
Slightly soapy water sprayed on the plants everyday for a week should control them. Misting every day is not a mistake.
Snails and Slugs - can eat collections and hide in the media. Put the pot in water for 24 hrs, the slugs/snails crawl to the top.
Diatomaceous earth, spread on the surface of the media, must be a bit dry to work.
Iron phosphate, is toxic to them but must be eaten. Scatter it on the media not on the leaves. Methaldhyde, the most toxic pesticide, should be scattered on the media surface, not on the leaves. Trying a bit of all will do the best job.
Squirrels and Rats/Mice - will eat a collection then go for lunch. Shot guns are not the answer. Seal any points of ingress to exclude them from your growing area. Use traps if they still can get in the growing area. Poisons get you a dead animals in inaccessible locations. Remember that rats/mice do damage at night and squirrels by day.