Shop for Coelogyne & Other orchids
The genus Coelogyne is comprised of about 140 species. Both the species and hybrids are relatively easy to grow and produce large sprays of long lasting, fragrant flowers. Coelogyne species are spread over a large region from India, through southeast Asia, southwest China, the Philippines, and the islands of Indonesia to as far east as New Guinea and islands of the southern and eastern Pacific.
Light and Shade
Coelogyne grow well in bright diffuse light, so that if a hand is passed over the leaves it produces a faint shadow. We recommend growing in east or west-facing windows. South-facing windows should only be used if shielded from the sun using a sheer curtain. If temperature highs remain below these orchid's limits, then Coelogyne can be grown outside from June to late fall in areas with filtered light, such as through a pine tree or shrub in early morning or afternoon. Be careful not to exposure these orchids to prolonged direct sunlight, as the leaves may sunburn easily. If using artificial light to grow indoors, LEDs are the best option. The artificial light market has expanded greatly in recent years, so a quick Google search will result in a variety of lighting options and price ranges.
Temperature and Humidity
There are both warm-growing and cool-growing Coelogyne species. Popular warm-growing species include C. asperata, C. fimbriata, C. flaccida, C. lawrenceana, C. mayeriana, C. pandurata, C. parishii, C. pulverula (syn. C. dayana), C. rochussenii, and C. usitana. These species and hybrids derived from prefer daytime temperatures from 75°F to 85°F (24°C to 27°C), and night temperatures between 60°F to 70°F (15°C to 21°C).
Popular cool-growing species include C. cristata, C. massangeana, C. mooreana, C. mossiae, C. nitida (syn. C. ochracea), and C. stricta (C. elata). These species and hybrids derived from them do well in the average home or a cool to intermediate temperature greenhouse. These orchids prefer daytime temperatures from 70°F to 75°F (21°C to 24°C), and night temperatures between 58°F to 65°F (14°C to 18°C). Some of these orchids will even tolerate winter temperatures down to 40°F (4°C), on the condition that the plant is dry.
If you keep your Coelogyne watered well, humidity will not be a critical factor in their growth. However, these orchids thrive under high humidity and will benefit from humidity levels above 50%. This can be achieved at home with the use of a humidifier or a humidity tray. Just make sure that the plant is not standing in water or the roots will rot.
Feeding
We highly recommend Green Jungle Orchid Food, specially formulated to provide orchids with the nutrients they would naturally encounter in their wild habitats. This is the fertilizer that we developed to use on our own plants in production, with excellent results for decades! This formula works best with water low in alkalinity (such as rainwater, distilled water, or reverse osmosis water). However, you may use tap water, keeping in mind that mineral buildup will require repotting more frequently, on the order of every 1 to 2 years. When potting in sphagnum moss, fertilize every 3rd watering year round.
Watering
Coelogyne should be watered heavily while actively growing, with little if any drying allowed between waterings. Water should then be gradually reduced after new growths have matured in autumn and limited in winter to occasional light waterings or early morning mistings. More water should be given if the tips of the youngest leaves start to die back or if the pseudobulbs show signs of excessive shriveling. The leaves on the older pseudobulbs may naturally die back during this time, but the tips of those on the newest growths should remain green. Likewise, slight shriveling should occur on the newest pseudobulbs. Too much shriveling indicates a need for more water and no shriveling at all indicates the plant may not bloom because of too much water. Water should be gradually increased in spring after new roots begin to grow. We always recommend watering in the morning, as this gives the leaves time to dry and avoid bacterial growth overnight. If possible, use water low in alkalinity, such as rainwater, distilled water, or reverse osmosis water. If you have a dehumidifier in your home, the water that collects in the tray is excellent for watering orchids.
Potting
Coelogyne orchids do best when potted using New Zealand Sphagnum Moss as the potting medium. These orchids tend to be less finicky than other orchid groups, so you may allow room for up to two year's new growth. Repot once every 1 to 2 years, preferably in the spring when active growth resumes. When repotting, choose a basket that is large enough to accommodate 1 or 2 years growth (2 to 3 new bulbs per year). If the moss is old, crumbly and sour, carefully remove the moss and rinse the root system. Trim off any dead roots. Position the plant with its oldest bulbs to the edge of the new pot. Then, spreading the orchid roots out, fill in the space with fresh sphagnum moss.
Coelogyne can be divided when there are 6 or more pseudobulbs. Should you wish to divide your plant at this time, each section should have three or four green bulbs in addition to any new leads. Old leafless pseudobulbs can be left on the plant, as these orchids are naturally deciduous You can watch our video on dividing orchids here.
To avoid the transfer of orchid diseases, it is standard procedure to sterilize all cutting and potting instruments before using them on a plant. This can be done by flaming pruning shears with a butane torch, or by spraying with rubbing alcohol and wiping with a clean paper towel.