The Aerangis genus comprises many tropical orchids which can be distinguished by their lovely white, star-shaped flowers. The genus contains about 50 plants, and though they mostly originate in tropical regions of Africa, a few are also native to the islands of the Indian ocean. Aerangis orchids, though uncommon in cultivation, are not overly difficult to grow, even by novices. However, they don't react well to sudden environmental changes, and like all orchids, plants are often lost to sudden changes in temperature or humidity.
Typically, these orchids are epiphytes—plants that grow attached to trees rather than in soil—and they’re often grown in hanging baskets filled with bark chip/ sphagnum moss mixture. The best and most distinctive feature of an Aerangis plant is its waxy flowers, which are usually white or yellow and shaped like five-pointed stars. Not only do these flowers give off a pleasant aroma, but they also bloom with regularity.
A single Aerangis specimen can bear many flowers at once. Their leaves are evergreen, and their spurs contain nectar that is pleasing to birds. Despite their relative rarity, several species of Aerangis plants, such as A. citrata, are sometimes grown by hobbyists, and there are also a few hybrids available to orchid aficionados and botanical experts. Gardeners who can mimic the tropical conditions in which the Aerangis orchid thrives will want to consider this understated and pleasant genus.
|Botanical Name||Aerangis spp.|
|Common Name||Aerangis orchids|
|Plant Type||Epiphytic orchids|
|Mature Size||6–24 inches (varies by species)|
|Sun Exposure||Part sun, bright filtered light|
|Soil Type||Orchid potting mix|
|Soil pH||5.5 to 6.0 (acidic)|
|Bloom Time||Spring to fall (varies by species)|
|Flower Color||White, yellow|
|Hardiness Zones||10–11 (USDA)|
|Native Area||Tropical Africa, Madagascar|
Aerangis Orchid Care
As is true of most tropical orchids, successfully growing Aerangis plants depends on maintaining a proper balance of the various elements on which they depend. They need a well-aerated environment, lots of sunlight, and lots of moisture in the air. Remember to feed them regularly, and if their blooms are insufficient you can always increase the fertilizer levels.
Aerangis plants are especially well-suited to grow vertically on a hard surface, so certainly consider mounting your plant if you grow one. These are fairly simple orchids that beginners should be able to grow with a little effort; just watch out for common orchid pests, like scale and aphids, that may prey on your plants.
These tropical orchids need lots of bright indirect light in order to thrive, but they don't care for direct sunlight. They prefer a bit more shade than other orchids, and the best environment will simulate the light of an open location location on a brightly overcast day.
A well-draining epiphyte mix is best, such as chopped sphagnum moss with styrofoam or wood chips. A standard orchid mix works well when growing these plants in hanging baskets. Good drainage is essential, as standing water will kill these plants.
Aerangis orchids need a very moist environment, especially when grown epiphytically. Keep them well-watered at all times. A thorough misting every day is often required.
Temperature and Humidity
These plants require warm tropical temperatures above 50 degrees Fahrenheit. These plants are not frost-tolerant, and they don't react well to sudden changes in temperature. In native locations, many of these species grow at higher altitudes in tropical zones, so they don't necessarily need the deep heat of jungle bottomlands. Nighttime temps in the 50- to 60-degree range and daytime temps from 70 to 80 degrees Fahrenheit are ideal.
These plants like humidity levels of at least 75 percent, so they will grow best in a greenhouse or terrarium environment. If grown in an open environment, plan on misting them every day with room-temperature water (not cold water).
Feed regularly with a balanced, diluted fertilizer during the growing season in spring and summer. Their fertilizer can be scaled back during the dormant season in fall and winter.
Aerangis Orchid Varieties
One relatively popular Aerangis is A. citrata, a variant from Madagascar with yellowish flowers. It’s from those flowers that it derives its name, which means “lemon-colored”.
Some other popular species include A. articulata, A. biloba, A. fastuosa, A. flabellifolia, A. mystacidii, and A. somasticta.
Also popular with collectors are the several hybrids, developed by crossing Aerangis with other orchid genera—the Aerangis genus hybridizes easily with Angraecum, Aeranthes, and several other orchid variants.
Potting and Repotting
Many people mount Aerangis plants on a sheer, vertical surface, like cork or hardwood. If you choose to grow your plants this way, repotting them won’t be necessary. However, they are often grown hanging baskets filled with a typical orchid mix that blends sphagnum moss and fine wood chips. In this case, it’s a good idea to change out the container once every few years. Lift the plant as a whole and try not to damage its root systems, which are fairly fragile.
Propagating Aerangis Orchids
These epiphytes can be propagated by division. Cut away a large section from the stem and replant it in warm, moist conditions. Many gardeners cover new divisions with bags in order to seal in moisture, and you can also treat the cuttings with rooting hormone. Be patient: It can take a little while for tropical orchids to root in a new environment.
Orchids can be temperamental plants, susceptible to many pests and diseases, which are more likely to occur when plants are in less-than-ideal cultural conditions.
Mites, mealybugs, and scale insects are common pests, best treated by dabbing them with a swab soaked in isopropyl alcohol.
Fungal or bacterial leaf spots often occur when the plant is too wet or too cold. Affected spots on leaves should be carefully cut away with a razor blade, with the cut edges of the leaves treated with a fungicide powder. These plants have sparse foliage, so this is usually not a difficult task. Viral infections can cause serious distortion of leaves, and affected plants will need to be destroyed.
Flower bud drop can be caused by too much or too little water, or temps that are too low or too high. Getting these conditions just right is the biggest challenge when growing orchids.