Crepidium (Malaxis) calophyllum

In a broader sense, 'jewel orchids' are all orchids cultivated primarily for their patterned foliage. In a narrower sense, the term "jewel orchids" refers only to the representatives of the subtribe Goodyerinae (nerve-leaf orchids), but some other, not closely related orchids are also referred to as jewel or ornamental-leaf orchids.

These are mostly terrestrial species that camouflage themselves with their patterned leaves on the forest floor. However, the term "terrestrial" usually evokes the wrong associations here. Most of these colorful-leaved, terrestrial orchids do not grow in classic, humic forest soil, as we know it from our latitudes, but on nutrient-poor clay soils with a minimal humus layer, or they grow on rocks, break edges, and similar places, not directly on the ground, but rather lithophytically. This must also be considered for long-term care.

The Jewel Orchid is a forest floor plant and accordingly does not require much light. A fairly dim illumination of 1,500 to 3,000 lux or 35 to 70 PPFD (µmol/m²/s) is sufficient for it. The leaves display their best color with less light, but then it also grows significantly slower.

It likes humidity of 70% or more. It can also grow in still air and 100% relative humidity, but then you have to be careful about standing water on the leaves. It likes it warm.

Temperatures of 22 to 28°C lead to the best growth. Especially with very moist substrate, the temperature should also be high, otherwise it tends to root rot. During the dry season, when it has no leaves, it can also be kept cooler. 12 - 15°C is not a problem.

This jewel orchid likes a rather coarse, airy, and evenly moist substrate. In nature, this plant grows in very nutrient-poor soil.

In the rainforest, there is little to no humus, as known from native forests. A thin layer of leaves/detritus, only 1 to 3 cm thick, is usually followed directly by dense clay soil or rock. The roots of the plants creep along the surface under the thin leaf layer and almost never go deeper than a few centimeters into the clay soil. This plant should therefore be potted in a loose, only slightly acidic (pH value of approx. 5.5 to 6.5) and airy mix. It grows very well in coconut chips mixed with some sphagnum moss or tree fern fiber. This is the same mixture that we also recommend as substrate for typical tropical terrariums.

It also grows well in a purely mineral substrate, such as our ASP mix, but we do not recommend repotting it immediately after arrival, as this can cause a lot of stress. Most of our plants are already potted in the substrates we recommend and can remain in them.

This species forms pseudobulbs that must not be buried in the soil. Only the roots should be placed in the substrate.

This orchid has a dry period in winter that must be taken into account when caring for it. After flowering, it should slowly dry out, and then it will naturally shed its leaves and retreat into its pseudobulbs. The dry period lasts about 2 to 3 months. New shoots will then appear at the base of the old pseudobulbs, and from then on, it can be slowly watered again. Once it starts growing, it can be kept consistently moist.

It prefers soft water from a reverse osmosis system or rainwater. Ideal conductivity is approximately 20 – 100 µS/cm.

During the growing season, it should receive orchid fertilizer (without carbamide nitrogen) approximately every 2 to 3 weeks, dosed according to the manufacturer's instructions (this corresponds to a fertilizer conductivity of about 500 µS/cm).