In almost every room in my house, at some point in the year, you will find an orchid in bloom. As the flowers reach colorful, delicate peaks, they're given a prominent spot in the kitchen, the home office, the sunroom or the bath until the blooming is finished, when they're returned to the greenhouse to replenish themselves.
Orchids have a well-deserved reputation for beauty -- and also for being temperamental. Even the most confident gardener may feel wary when it comes to caring for any one of the 30,000 orchid varieties, which thrive under different conditions, in different climates.Most orchids grow in the tropics, but not necessarily in the humidity of the rain-forest floor. Instead, orchids can usually be found in the cooler, midmountain tropical ranges, some of them growing on treetops in search of direct light, others in the diffuse light of lush undergrowth or on tree trunks where they're subject to cool, moist breezes.
Only a small portion of the world's orchids are suitable for growing in our homes. But don't let that intimidate you. The key to success is choosing the right orchid for the conditions you have to offer.
Orchids don't lend themselves to impulse buying. No matter how beautiful their flowers, if the conditions in your home aren't right, you won't be able to coax those flowers out. The violet-colored Ascocenda Pacific Blue, with its huge flower display, thrives in the bright sun and fresh air of a Florida climate. A moth orchid or Phalaenopsis does better in diffused sunlight and is better-suited for a perch on an apartment windowsill.
It's essential to obtain your orchid from a good dealer who can help you make a knowledgeable choice. Catalogs and retail greenhouses often rate orchids by their level of difficulty and will spell out exactly what an orchid requires with respect to light and temperature demands.
Before you purchase an orchid, evaluate the windowsill where it will grow for light. Place your hand about 6 inches above the position the plant will occupy and observe the shadow. A crisp shadow indicates high light levels, while a softer shadow denotes low to medium light. If there isn't a shadow at all, the chances of successfully raising an orchid are pretty slim; even an orchid that grows with low light levels will still require around eight hours of daily exposure.
Here are a few basic points to remember when cultivating an orchid.
Humidity: Check the level of humidity in your home; 40 percent or better is the level that encourages the healthiest growth. Radiators and air conditioners can upset humidity levels, and you will need to compensate for any fluctuations by standing the orchid above water-filled pebble trays, misting the orchid regularly or running a cool humidifier. You can purchase an inexpensive hygrometer from a florist or cigar shop to keep tabs on your room's humidity.
Some orchids do especially well in semi-enclosed glass cases or fishbowls, but usually not in a true terrarium, which can suffocate the plant.
Watering methods and potting mediums: The best watering methods and potting mediums will vary from orchid to orchid. Orchids that grow on the ground (terrestrials) will need a medium that retains water longer than an orchid that grows in trees (epiphytic). The former do well with a blend of sphagnum moss, fine bark and sharp sand. The latter flourish with a medium composed of bark, pumice or perlite and chopped sphagnum.
The focus of the watering should be on the potting medium, not the flowers and foliage. Flood the pot with water that's warmer than 50 degrees Fahrenheit, and let it drain before putting it back in its place. You can also alternate in six-day intervals between pure water and a mixture of water and blossom-booster fertilizer at half the recommended strength.
Repotting: When the bark pieces begin to break down or the roots exceed the size of the container, it's time to repot. The best method is to time the repotting so it coincides with the first sign of the root tips turning green, usually in the spring.
Continue to meet its needs, and the beauty within each orchid will amaze you year after year.
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