By Dan Gill
LSU AgCenter Horticulturist
(12/15/17) I have a small collection of orchids that are a delight to me. A common misconception is that orchids are difficult to grow. In fact, orchids are tough, resilient plants, and most are not that challenging if you just learn the growing conditions they prefer. Growing orchids comes to my mind now because they are sometimes given as gifts over the holidays, and one of my favorite orchids, the moth orchid, is a readily available and popular choice for gift-giving.
Moth orchid is the name given to plants that belong to the genus Phalaenopsis (pronounced: fail-en-OP-sis). As a group, they are relatively easy to grow and are a good choice for a beginner’s first orchid. The genus name is from the Greek for “moth appearance.” The first species discovered produced beautiful sprays of white blooms that resembled big moths in wide-winged flight. With the discovery of new species and the development of hybrids, the color range goes well beyond white and includes white with a colored lip, pink, yellow, green and red, with spots, stripes or bars in many different combinations.
About 40 to 50 species are found from the eastern Himalayan Mountains to Australia, with most native to the warm Philippine lowlands. They typically grow epiphytically, with their roots attached to trees or on rocks, in warm, humid, shady locations.
The plant growth habit is attractive, with low-growing, elongated leaves rising in opposite directions from a central crown. Plants send up leaves individually during periods of active growth, and as they do, older leaves will tend to yellow and should be removed. Usually, a plant has not more than three to five leaves at one time. In some varieties, the leaves are attractively marked with silver, but for most, the leaves are mid- to dark green and leathery.
The classic phalaenopsis has long, pendulous flower stalks bearing a number of large, rounded white or pink flowers. But many species and hybrids produce flowers in a wide variety of colors and forms, including small flowers in large branching clusters and short upright spikes. A well-grown plant can send up multiple flower spikes. Each bloom can last a month or more, and a plant can flower for months at a time.
Indoors, they will thrive in a brightly lit window facing east, south or west. A shady north-facing window may not provide enough light to encourage blooming. You can summer your plants outside during warmer times of the year. After nighttime temperatures reliably stay above 55 degrees, move them to a shady spot that receives no more than a couple of hours of morning sun or dappled light (too much direct sun will burn the foliage). Spending time outside also provides a temperature drop between day and night of at least 10 degrees, which these orchids prefer.
Phalaenopsis, like many orchids, are epiphytes (like resurrection fern and Spanish moss) that do not grow in soil but upon the branches of other plants. When grown in containers, they must be planted in a special orchid mix. Orchid mixes are generally based on chopped fir bark these days. Phalaenopsis should be potted in a medium grade bark or medium-fine bark mix (medium bark with perlite and chopped sphagnum moss added).
These special mixes greatly influence how we water orchids. To water orchids, you must run water through the mix until it is properly moistened. This cannot be done with the plant sitting on the windowsill because water would go all over the place. It is best done indoors at the sink, allowing warm water to flow through the mix until it is thoroughly moistened. Outside, just use a hose. Unlike some orchids, phalaenopsis do not have water storage organs and should be kept moist, letting them dry only slightly between waterings.
These orchid mixes also contain very little in the way of nutrients. To keep your phalaenopsis growing vigorously, fertilize them monthly from spring to early fall using a soluble fertilizer, such as 20-20-20, according to label directions.
It is important to remember there are many kinds of orchids, and each type has its own preferred growing conditions. It’s really not all that complicated. But it is important to know the type of orchid you have when trying to learn how to grow it. If you should receive one of these wonderful plants as a gift, make sure you save the label with the name of the plant on it. It will help considerably when you start researching how to care for your new orchid.
Orchid. Photo by Rick Bogren/LSU AgCenter
Orchid. Photo by Rick Bogren/LSU AgCenter
Orchid. Photo by Rick Bogren/LSU AgCenter