Orchids as Houseplants

Orchids make wonderful plants for decorating the home. The flowers are colorful, unique, and long-lasting. Orchids may have a reputation for being difficult to grow indoors, but by selecting certain genera and providing the proper environmental conditions, success is almost guaranteed. Some orchids that require high light, high humidity, or cool humid conditions may prove difficult to grow indoors. What orchids then will grow well in the conditions of the average home? There are two genera of orchids whose requirements are similar to those of most homes. They are Paphiopedilum and Phalaenopsis.

Paphiopedilum (left) and Phalaenopsis (right). Photo credit: E. Jay Holcomb

Paphiopedilum (Paphs), called slipper orchids, grow on the shaded floor of tropical forests where temperatures are warm and the humidity is high. Indoors, slipper orchids generally require a temperature range of 60°F at night to no more than 90°F during the day. In their natural environment, the light requirement is low; translated to the home, site the plant in an east or west window. A north window will probably not have enough light. Paphs also do well under artificial light. 

In their natural tropical forest habitat, the leaf litter where they grow generally does not dry out completely. We can replicate this by watering them frequently enough to keep the potting media moist but not soggy wet. The potting mix should be a very open, well-drained mix that does not dry out too quickly. There are many mixes on the market so choose one that drains rapidly but does have some water holding capacity. Growing media with bark as the primary component generally drain fulfill these requirements.

Slipper orchids prefer high humidity but that is very hard to duplicate in the home. Most homes have a fairly low humidity due to winter heating and air conditioning in the summer. In my experience, most Paphs will tolerate the low humidity and will grow and flower.

Most orchid potting mixes do not have enough fertilizer in the media, so fertilization of the plants is necessary. A water-soluble houseplant fertilizer used at one-half of the manufacturer's recommended rate once or twice a month is adequate. If you provide the orchids with adequate light, water, and fertilizer, they will produce spectacular flowers about once a year.

Phalaenopsis (Phals), commonly called moth orchids, typically grow on trees and are located in the shade of the warm and humid tropical forests. To duplicate these conditions, provide low light, warm temperatures, moist growing mix, and high humidity. In the home, Phals will do best in an east or west window. Although, I have had success growing them in a south window as well. Moth orchids can also be grown under artificial light--except the tall flowering spike may hit the light bulbs. The temperature for Phals is a minimum of 60°F at night and a maximum of 85°F during the day. If your house is about 65°F during the winter and 75°F during the summer, Phals will be very happy.

Since Phals grow on trees, the growing mix should be very well-drained with lots of aeration. Some Phals that you may purchase will be growing in sphagnum moss, and if they need to be repotted, they can also be grown in fir bark. The media can dry out a little between waterings. Sometimes the roots seem to prefer growing in the air rather than the pot. I often mist these roots each morning so that they do get some moisture, although it is not necessary. Moth orchids require fertilizer and it can be applied at the same rate used for slipper orchids. These plants also prefer high humidity, but usually will tolerate the humidity of the home. I have had some Phals that have dropped one or two flower buds from the spike that was due to low humidity; however, most of the flower buds did open. The flowering of Phals is related to the species. There are spring-flowering Phals and summer flowering Phals; however, they have been cross-pollinated enough so that the Phal that you purchase will probably flower once a year. The spring flowering Phals seem to have larger flowers. (See lead image.)

Both Paphiopedilum and Phalaenopsis orchids require growing conditions similar to those that occur in the average home and both of these orchids make beautiful indoor flowering plants.