Elegant, showy orchids have some of the most detailed flowers ever seen. The stunning blossoms last for weeks, even as cut stems. Despite their reputation for being finicky, they can make great houseplants.
HOW ORCHIDS GROW
The Orchidaceae is the largest family of flowering plants in the world, with more than 25,000 known species. Orchids occupy a broad range of habitats and are found on every continent except Antarctica. Most people think of orchids as epiphytes growing up in the tree canopy in the tropical rainforest, but many are happy in soil, including our native lady’s slipper. These terrestrial orchids are most commonly found in the temperate and arctic regions, with many of the terrestrial orchids of the U.S. and Canada inhabiting cool, damp bogs, as well as sandy plains, mountainous terrain and moist grasslands.
Most of our American species grow in symbiosis with fungi in the soil. This partnership makes it all but impossible to successfully transplant wild, native orchids into a garden setting or to grow them from seed in a nonnative setting. Hardy orchids for your garden are best procured from a reputable dealer who produces them from tissue culture or stock plant division and never digs wild plants or collects their seed.
The diversity in orchids also includes very complex relationships with their pollinators. Peter and Paul Ehrlich developed the theory of co-evolution, which is the concept that plants and pollinators evolve together. Orchids are masters at this. A few species are self-pollinating or fertilized by pollen carried on the wind, but most require a specific animal to pollinate them. Orchids use scent—both good and bad— to attract these partners, with sweet-scented flowers attracting bees, butterflies or hummingbirds, and foul, carrion-scented flowers attracting flies. If an orchid species loses its coevolved partner due to habitat destruction, it is likely that it will not be able to set seed again and will be doomed to extinction.
HOW TO GROW ORCHIDS AT HOME
The complicated biology of orchids may make you think they are not well-suited as houseplants, but by careful selection of appropriate types, you may have a beautiful display of orchids at home. Many orchids are relatively easy-to-grow houseplants. You will need to determine if your selection is terrestrial or epiphytic so you know what growing medium to plant them in. Bark chips are used for epiphytic types. And find out what their light requirement is—low, medium or bright light— to find the right exposure. Many species are quite content in a bright east or south window with a little protection in the form of a sheer curtain or blind. West windows will need more screening. Healthy leaves should be bright green—too dark and it’s insufficient light; too light or reddish and it’s too much light. If the leaves start showing black spots, your plant is getting too much direct sun.
For watering, once a week in the winter should be sufficient, but bump it up to twice a week when the weather is warm and dry. Check with your source on the watering requirements for your particular orchid—some like to be consistently moist, some like to dry out between waterings and others like to be kept a little on the dry side. Humidity also is a factor to be considered. When it’s very warm, you can place the plant on a bed of pebbles in a water-filled saucer to increase the humidity around the plant. I mist mine with a small sprayer frequently, and they do very well. But don’t let any orchid plant sit in the water—it will rot the roots. Bright yellow leaves are often an indication of overwatering.
Fertilization is important for flower production and overall plant health. There are many fertilizers specifically formulated for orchids. Follow the instructions on the fertilizer—too little fertilizer and you can stunt its growth; too much and you can burn the roots and inhibit flowering. Most orchids also need a 10- to 15- degree day/night temperature fluctuation to initiate flowering— somewhere between 60 and 65 degrees at night and 70 and 80 degrees during the day. A constant cool to moderate temperature will help flowers last longer once they are open.
VISIT THE ORCHID SHOW
The annual Orchid Show at the Missouri Botanical Garden is an excellent place to see many different species and cultivars of orchids.
The Garden’s collection is one of the oldest, richest and largest in the nation, and the show will include 800 blooming orchid plants laden with thousands of flowers.
The show is an indoor Chinese strolling garden with architecturally inspired elements. Begin by walking through the Moon Gate (a replica of the iconic, rounded entrance to the Garden’s Grigg Nanjing Friendship Garden) to enter a green landscape infused with Chinese-themed accents and studded with orchids. Stroll along curving paths bordered with several water features, little stone lanterns and statuary. Dozens of large, tasseled silk lanterns hang overhead and add bright and lively punches of color. Bamboo shoots are trained into stylized decorative arrangements. Stone details include a small footbridge and classic pagoda that are surrounded by masses of orchids and greenery. Huge specimens of the terrestrial Phaius and Cymbidium rise up out of beds as they would in nature. Epiphytes like Cattleya, Oncidium and Epidendrum are displayed in hanging baskets or on trees much as they would be found deep in tropical rainforests. Other varieties on display include Paphiopedilum and Laelia, with many bi- and trigeneric hybrids featured. Orchids have been hybridized for generations, and many very showy floral types have been added to the rich natural catalog of wild species. Accent plants and backdrops in the show are created from other plants appropriate to a Chinese setting, including bamboo palms (Chamaedorea seifrizii) and heavenly bamboo nandina (Nandina domestica).
Orchids are a fascinating family of plants. Our all- American favorite flavor, vanilla, is made from the seed pods of a vining tropical orchid. In China, orchid flowers, stems and seeds are used as medicine and tea. My favorite potted orchid, Phaius tankervilleae (the nun’s orchid) is found in Yunnan, China. I’ve grown Phaius, Miltonia, Oncidium and moth orchids on my window ledge and successfully re-bloomed them. Even if your home habitat is not perfect, a specimen with buds on it when you get it may last for several months.
For the outdoor garden, try my favorite: Bletilla. It comes in a shocking fuchsia and naturalizes well in a woodsy garden. They are reliably winter hardy here. Visit the English Woodland Garden in the spring to see them displayed in lovely drifts. Because most orchids are considered ‘exotic’ and ‘hard to grow,’ they give great cachet to your gardens. But we know much more now about how to make them thrive. Try them. You will fall in love with their graceful elegance.
ORCHID SHOW AT THE MISSOURI BOTANICAL GARDEN
Stroll through the lush, tropical landscape of fragrant orchid blooms on Saturday, Jan. 28, through Sunday, March 25, from 9 a.m. to 5 p.m. daily. Show admission is $5, in addition to regular Garden admission. Visit mobot.org to learn more.
Patricia Raven, Ph.D., has a doctorate in ornamental horticulture and Julie Hess is senior horticulturist at the Missouri Botanical Garden.