The Dendrobium genus of orchids is prolific, with more than 1,000 species that are divided into deciduous and evergreen, and those are divided into warm- and cool-growing plants. Dendrobium orchids are an excellent choice for the beginning grower as they are easy to care for and can have long lives if properly fed and watered.
The Dendrobium orchid is bulbless and has longer stems than other orchids; these heavy cane-like stems produce papery leaves. The flowers are available in a wide range of colors — including purple, white and multicolored — sizes and shapes and will stay open for a couple of months. The Dendrobium orchid is sometimes called "Phalaenopsis type" because it looks like the flowers of the Phalaenopsis type, but it isn’t a close relative and doesn’t have the same characteristics.
Sun and Temperature
Dendrobium orchids enjoy full morning and late afternoon sun but need some shade later in the strong morning and early afternoon sun between 11 a.m. and 3 p.m. The ideal temperature during the day is between 75 and 90 degree Fahrenheit, and the nighttime temperature should range between 60 and 65 degrees F. Protect the orchid from extreme temperatures; occasional exposures are tolerated if not prolonged.
Watering and Humidity
Dendrobium orchids will not grow if the roots are in soggy soil, so let the soil dry completely between waterings. This should work out to watering the plant once or twice a week — or more in the heat — early in the day. The plants do best at 40 to 50 percent humidity. If the conditions are dry, you may need to use a humidifier or humidity trays.
Potting and Fertilizer
Plant your Dendrobium orchid in a well-draining potting soil with medium-grade fir bark. Add a fertilizer that is formulated for orchids to the soil of your Dendrobium once a month. Make sure not to overfeed as you might burn the roots and stunt the blooms. Repot your orchid once every two years — preferably in the spring or when new growth starts.