Orchids have a reputation of being exotic plants that are difficult to grow. Exotic plants they certainly are, but provided you learn the three essentials and apply them orchids can be grown successfully as houseplants. I found an article by Alex Vasiljev in the Fine Gardening magazine which explains the three keys to success and then gives illustrated instructions on how and when to repot your orchid.

I got my first orchid plant at age 12, when I was growing up in the Ukraine. An orchid?s ability to root and grow entirely above the ground fascinated me. I soon acquired a collection of orchids that I grew indoors, and my interest eventually turned into a profession. With their unusual growth habits and enigmatic blooms, orchids have intrigued humans for thousands of years. However, most of what we know about orchid culture has been accumulated over the last 200 years or so.
Many of the orchids brought to Europe by plant hunters in the early 18th century were epiphytes. Also known as air plants, epiphytes grow on other plants without connecting to the ground or harming their hosts. European growers, however, kept them in hot, humid, unventilated houses, which proved devastating for the orchids. The legend that orchids were difficult to grow began in that era, and it took almost 100 years for growers to develop successful methods for tending them.
Now we know that many orchids are as easy to grow as African violets. The easiest to grow indoors are epiphytic? the same orchids considered so stubborn and uncooperative by early British orchid growers.
Here, I will focus on growing orchids indoors?specifically those that thrive best under average conditions in a home environment. The keys to success are knowing an orchid?s needs, choosing an orchid based on the conditions you can provide, then giving it the right care.

Orchids vary in their temperature preferences

Temperature affects an orchid?s overall growth and especially its bloom habits. The most critical time for orchids is during the winter, when many of them are preparing to bloom. Orchids are classified into three types based on their winter temperature needs: cool-, intermediate-, and warm-growing.
Cool-growing orchids enjoy night temperatures in winter around 50?F and daytime temperatures not exceeding 70?. Intermediate-growing orchids prefer minimum winter-night temperature around 60? and daytime temperatures from 70? to 85?. Most orchids best suited for growing indoors are in the intermediate group (see sidebar). Night temperatures for warm-growing orchids should not be lower than 65?, and daytime winter temperatures can range from 75? to 85?. During the summer, intermediate- and warm-growing orchids can stand temperatures up to 85? or 90? as long as they have good air circulation. Cool-growing orchids prefer to stay cool in the summer.
A fluctuation of 10 to 20 degrees between day and night temperatures is essential for all orchids and triggers them to produce flowers. This difference is most important for cool- and intermediate-growing orchids because of the conditions they are used to in the wild. In the winter, it?s possible to achieve this fluctuation by lowering your home?s thermostat or by moving an orchid to a cooler spot, like a porch or a garage, at night.
Most orchids flourish under bright, indirect light. Full eastern or western exposure or indirect southern exposure usually provides enough light. However, as with temperature, specific orchids may require a certain light intensity. When buying an orchid, check the label for its light preference, then observe how much light your orchid actually receives.
Symptoms of excessive light are sun burn, yellowish foliage, and a plant that looks weak and dehydrated. On the other hand, if you bought an orchid in bloom and it did not rebloom the following year, even though the foliage looks green and full, consider giving it more light. Also make sure the temperature range is correct.
Read more: Fine Gardening
Image source: Susanne Nilsson