Joe Peterson, who has grown orchids for 30 years, gave our October educational talk. He says they are easy to grow! There are 30,000 species of orchids and 100,000 hybrids, and they grow on every continent except Antarctica in a wide diversity of climates from sea level to 12,000 feet.
Hybrids are easier to grow for the house plant fancier. They often need high sunlight, so growing them in a north window is not recommended. The American Orchid Society’s website has culture sheets on most of the genera. Joe uses plastic pots.
Phalaenopsis, native to Southeast Asia, is the most popular orchid (nicknamed “moth orchid”), and the plants we buy here are mostly grown in Taiwan. In their native habitat they grow on the sides of trees near the bottom of the jungle, so they need low to medium light. Their exquisite blooms last 6-12 weeks. When you buy them, they should be in bud so you know you will enjoy them for their full bloom time. After they finish blooming, cut off the flower above the first notch. Daytime temperature should be 70-85 degrees with night temperature 60-65. They need to be watered once a week with a weak fertilizer solution. There are two causes for a lack of flowers: day length is too long and there is no nighttime temperature drop. One solution is to move them outside to a shady spot off the ground for two weeks in September or leave them near an open window or air conditioning unit.
Paphiopedilums, also native to Southeast Asia, are either bulldog types like lady slippers or multi-florals. The bulldog types grow on limestone cliffs in the wild, and hybrids are suitable for home growing under low to medium light. Temperature requirements are the same as for phalaenopsis. They need a little more water, every 5-7 days with weak fertilizer. They need yearly re-potting in fresh bark without potting soil. Blooms last 4-6 weeks. Multi-florals last 2-6 weeks per inflorescence and can be up to 36” tall with some flowers being 8” x 12”. They need more light to bloom and can be quite expensive because they are slow-growing. Water every 5-7 days and re-pot annually. South American cousins to paphs have similar care requirements except that they need water twice weekly. Inflorescences can be 36” long.
Cattleyas are native to Central and South America and are often used as corsages in a wide variety of colors. They need medium to high light and are often grown in a greenhouse. Flowers last 2-3 weeks. They should be watered thoroughly then allowed to dry for 7-10 days with a weak fertilizer solution. They can summer outside in light shade but are susceptible to scale and mealy bugs.
Dendrobiums originate in Asia, Indonesia and Australia and are highly diverse with 1300 species. Their flowers last several days to several months. They need high light and a winter rest with no water for about 2 months. They are so diverse that the grower needs to research the specific variety for care instructions.
Oncidiums come from Central and South America and are familiarly known as “dancing ladies.” They need medium to high light and slightly cooler temperatures. Water and fertilize more heavily in the growing season.
Cymbidiums come from Southeast Asia. They are large, easy to grow and have spectacular blooms. They are often grown in California.
Some orchids can be grown in our gardens, and some are native to Michigan. They have very specific soil requirements, and you need expert advice to grow them. The tubers need to be dug up before winter.
As previously stated, the American Orchid Society has very specific culture sheets for all the major kinds of orchids on the website.