Mt. Lebanon Public Library program focuses on growing orchids
The colorful, fragrant blooms of orchids are what attract us to them today.
But that wasn’t always the case.
“The name ‘orchid’ comes from the Greek word ‘órkhis,'” Demetria Marsh said, elaborating on one reason why the ancients opted for that nomenclature: “They pulled them up, ground the tubers and used them as their first form of Viagra.”
Harry Funk / The Almanac
Welcome to Growing Orchids 101, Marsh’s recent program at Mt. Lebanon Public Library. As program chairwoman and past president of the Orchid Society of Western Pennsylvania, she enjoys sharing her knowledge of the Orchidaceae family of flowering plants, including highlights of its 90 million-year history.
For example, difficulty in growing orchids led them to be relatively rare and expensive until the mid-20th century.
“Things have really changed, and some of that is what scientists have learned and the fact that right now, orchids are second commercially only to poinsettias. So it has become an international, huge market,” Marsh said. “Luckily, it has made all these orchids available to us at more reasonable cost.”
One aspect of orchids that botanists have come to understand more thoroughly is that the plants are epiphytes, deriving their moisture and nutrients primarily from the air.
“So if you took your orchid and put it in soil because that’s what you thought would be good, you have a very low probability of growing that plant successfully,” Marsh explained. “They really need to have air around their roots.”
Harry Funk / The Almanac
Her suggestion is to use bark for potting the plants, and she noted that sphagnum moss also works, but it tends to break down quickly and not allow for air circulation.
Watering the plants, of course, is an important consideration.
“They like to have water really thoroughly, and then they need to dry out a little. And depending on what kind they are,” Marsh said about the 20,000-plus species of orchids, “is how long that drying-out period is.”
In general, she advises placing plants in a sink for watering, doing so thoroughly and then repeating the process after several minutes.
“The second time really helps the bark soak, because it takes a while for dried-out bark to start to absorb water,” she explained.
Her recommendation is to water plants twice a week, also depending on the type of orchid, and to ensure they receive enough, but not in excess.
“The worst thing is if you have rotted the roots because you gave it too much water,” she said. “And now there are no roots to give the plant water.”
As is the case with all plants, orchids need sunlight for photosynthesis, and how much depends on the type. Marsh provided some guidelines for lighting and other aspects of growth:
- Phalaenopsis (moth orchid). Lower light, eastern or western exposure, similar to African violets. Like to dry a bit between watering. Medium bark. Warm.
- Paphiopedilum (Venus slipper). Lower light, eastern or western exposure, similar to African violets. Like to stay evenly moist. Seedling bark. Warm.
- Dendro
- bium
- (evergreen type). Higher light, southern exposure, similar to gardenias or hibiscus. Like to dry a bit in between watering.
- Seedling bark. Never overpot. Warm.
- Oncidium
- . Higher light, southern exposure, similar to gardenias or hibiscus. Like to dry a bit in between watering. Medium bark. Intermediate temperature.
- Phragmipedium (genus of lady’s slipper). Higher light, sou
- thern e
- xposure, simi
- lar to gardenias or hibiscus. Water every day. Seedling bark. Intermediate temperature.
- Cattleya. Higher light, s
- o
- uthern exposure, similar to gardenias or hibiscus. Like to dry thoroughly in between watering. Medium bark, clay pot preferred. Intermediate temperature.
- Cymbidium (boat orchid). High light, full sun. Wet and hot in summer, outside: May through October. Dryer, no fertilizer and cold September and October outside. Must go down to 45 degrees at night in the fall, but not much lower. Bright light, and dry thoroughly in between waterings in the house during winter. Cold.