Rhynchostylis gigantea orchid | Orchid care | Foxtail orchid
This slow-growing monopodial orchid is native to southern China and southeast Asia, where it grows in the tropical understory. The color of the flower can be white, red, purple, blue, pink, or orange. While the foliage resembles that of a Vanda, it prefers more shade and the flowers are different, forming a long curving inflorescence of many fragrant flowers. This gorgeous floral display has earned it the common name ‘foxtail orchid’. While the lack of pseudobulbs means that these orchids cannot use them to store energy and water, their roots are much more fleshy and substantial than those of Vanda orchids, which allows them to resist drought conditions for much longer.
Rhynchostylis gigantea grows much slower than the other orchids. However, it is not difficult to grow, you just need to create a suitable growing environment. Here are a few tips.
Rhynchostylis gigantea thrives in a when the daylight temperatures hover around 90 F and dips down to about 75 at night, though it can tolerate much wider ranges so long as the temperature doesn’t fall below into the 50s. The dip in temperature at night triggers flowering.
In their natural habitat, Rhynchostylis orchids grow in the understory, where the bright tropical sunlight is filtered through the leaves of the canopy above. Vanda grow higher up, so it makes sense that these orchids require more dim light than what a Vanda requires, and that they will burn if kept at the same bright level. That being said, if you live in a northerly area winter light in the morning and evening will not damage it. We like to grow these orchids farther back from the windows than our Vanda and Ascocentrum - about 2000-2500 foot candles is a good range if you are measuring. I have also seen some people growing Rhy. gigantea under lower light like a Phalaenopsis. The leaves will be dark green but they can still flower. We can tell if the orchid needs more or less sunlight by the color of their leaves. Yellow leaves or leaves with black spots means that the orchid get too much sunlight. Dark green leaves indicate that the light is not sufficient.
Rhynchostylis gigantea likes to be watered abundantly from spring through autumn, when it is actively growing. The soil should not completely dry between waterings, especially while blooming. At the same time, the air should be kept moving to prevent rot. During winter dormancy, watering should be dialed back so that the media dries out completely in between waterings. We grow ours in a basket, and spray them every day in the spring and fall, sometimes twice a day on hot summer days. In winter, we spray them every two days. The pH of the water used for this orchid should be between 5.5 and 6.5. We just published a video showing how to measure water pH and control water quality for orchids. If you are growing orchids or plan to grow orchids, I highly recommend that video. You can click the link on the top right corner to check it out.
Rhynchostylis orchids love humidity - especially in the summer. Our sun room is typically in the 70s, sometimes in the 60s or 80s. This orchid will thrive in high humidity, but the air must be kept moving as stagnant air and high humidity can be a recipe for rot. It is a bit more tolerant of low humidity in the winter - usually around 70% is fine.
These orchids will appreciate a fairly standard fertilization regimen - dilute applications every week in the summer. More nitrogen-rich fertilizers in the spring and summer with a bit more phosphorus in the fall will help the plants to bloom.
We grow our Rhynchostylis in baskets with some coconut fiber and a little big of sphagnum. However, it might not be feasible to grow them in baskets in a more dry area, so some people use charcoal or bark to grow these orchids. However, keep in mind that the roots are very thick and sturdy, and are much less flexible than those of a Vanda. This makes them difficult to repot, so make sure that you are not creating a situation where you will have to repot them often as they are already slow-growing to begin with and need to be established for a while in order to stay healthy.
