Getting Started with Orchids
Susan Mahr

Orchids have a reputation as being difficult, if not impossible, to grow, especially without a greenhouse. Like any other plant, orchids must have the growing conditions they need to survive. But most orchids are actually far sturdier, adaptable, and resilient than most people think. If you can grow houseplants, you can grow orchids. There are some notoriously fussy orchids among the 20,000 species and over 100,000 hybrids available today, but if you select one of the rugged, popular, easy-to-grow types that adapt to the temperatures and light conditions found on the average home windowsill, orchids can be very rewarding indoor plants.

Orchids are different from other houseplants. Most orchids originally came from the tropics, primarily in the cloud forests, where they lived as epiphytes ("epi" = on; "phyte" = plant). These epiphytes live attached to other plants or structures that simply provide a place of attachment, but no water or nutrients. Since they do not have a continuous supply of water, their roots have a spongy coating that quickly soaks up the water from periodic rain or dew. Water is stored in their thickened leaves and stems so they can survive dry periods.  Orchid growers have to provide support for the plant, without allowing the roots to staywet. Indoors this can be accomplished by growing the orchid in a pot filled with chips of bark, stones, tree fern fiber or some other loosely packed material that allows the roots to be well-aerated and through which water can drain quickly. Potting an orchid insoil or letting it sit in a a water-logged pot will kill it, since a lack of oxygen will cause the roots to suffocate and rot. But you may have to experiment with different types of potting media to find the type that is best under your conditions.

Orchids in medium-sized pots generally need watering only once a week. They should be allowed to dry out before watering again. It's better to err on the dry side than to overwater. Of course, temperature, humidity, pot size, potting medium and many other factors influence how quickly your plants will dry out. Check frequently at first untilyou've figured out what is an optimal watering schedule for your plants.

Orchids are usually classified as warm growing, intermediate or cool growing, but most tolerate exposure to a wide variety of conditions without suffering (although most don't do well when temperatures remain constantly above 90°F). The classification refers to the minimum temperature the orchid prefers during winter nights. Cool growers, such as cymbidiums, do best when nights drop to about 50°F, while warm growers, such as phalaenopsis, don't like it much below 60°F at night. Intermediate types, such as cattleyas, prefer night time temperatures between those two.

Most people's first orchid is purchased in bloom. To get the plant to produce flowers again you have to provide a big difference between day and night temperatures, just like the plants would experience in nature. Making sure the temperature drops at least 10 degrees at night, especially in the fall and winter when many orchids initiate flower buds, will make it much more likely that your plant will reflower. Investing in an automatic setback thermometer can make this a lot easier (and probably save you some money in the long run). Your orchid plant will live quite nicely without this nightly  temperature drop, but may not do much more than that.

Optimal humidity also enhances flowering. Fifty percent or more is necessary, but often is far below that in most homes in the winter (summer is another story). You can increase humidity near the plants by using a humidifier; or try placing the pots on flat pebbles or pea  gravel in a tray filled with water so it almost covers the stones; or group the plants together and surround the area with clear plastic (it may not look so great in the living room, though). But beware too much humidity promotes fungal and bacterial diseases that can affect the leaves or flowers. In nature these pathogens are not a problem as the plants are normally in an environment full of breezes. You can use a small oscillating fan if necessary to simulate these conditions and prevent disease problems.

Orchids are also classified into three groups (high, medium, and low) depending on how much light they need to thrive. Most orchids prefer at least 6 hours of light a day. Although they will grow acceptably with less light than recommended, they may not flower if they receive inadequate light. How can you tell if your orchid is getting enough light? Lush, rich, dark green leaves are attractive, but indicate the light is not strong enough. The leaves should be a grassy green color (light or medium green with yellowish tones). You can determine if the light is sufficient for your orchid with a simple hand/eye test. Place your hand 6 inches above the leaves and look at the shadow that is cast. A sharp-edged shadow means high light; a soft-edged shadow indicates medium to low light; no shadow at all means the light is insufficient for an orchid to flower.

To provide optimum light indoors, place your plants in a south- or east-facing window. A western exposure is often too hot in the afternoon and north-facing windows are usually too dark.  Up here in the north, the sun shifts in the sky considerably, so you may have to move your plants as the seasons change to get the right amount of light. You can alter the amount of light the plants receive by moving them from or toward the window, putting up a sheer curtain to cast light shade in a too-bright spot, or placing reflective material in a dark growing area to increase usable light. Be careful that your plants don't get too much direct light – especially if they have tender, dark green leaves. Just like tender, unconditioned human skin, the leaves can be sunburned, first bleaching out to white, then dying and turning black.

If you don't have adequate light or space by your windows, you can always use artificial light. Special grow lights, or four fluorescent tubes placed 6 inches apart side by side and placed 6 to 8 inches above the plants, set for 14 to 16 hours a day should be sufficient for low light-requiring orchids.  Supplemental fluorescent light in a window may be all you need to provide sufficient light for your orchids to flower.

In the summer you can consider moving your plants outside. There they will be exposed to much higher light intensity (but be cautious about sunburn!), natural rainfall, and fluctuating temperatures that can promote flower bud initiation. We built a special shade structure (our "Orchidarium") for our plants to live in the backyard from about May to September, but hanging orchids from the lower branches of mature trees with sparse foliage or placing the plants on the ground under trees with denser foliage may work well, too. Just remember to consider what type of pests you may be inviting into your plants. Ants invaded several of my pots one year and set up housekeeping in the bark (it didn't affect the plants, but they were a nuisance when we moved them back inside); last year rodents nibbled off all the leaves of a phalaenopsis (it produced new leaves, but it'll be a while before it's big enough to flower again); plants sitting directly on the ground are prime spots for slugs to take up residence (and they could nibble leaves).

Fortunately orchids are relatively low-maintenance plants. It's recommended that you fertilize them weekly with a dilute solution of 20-20-20 fertilizer, then switch to a blossom-booster fertilizer (that has more phosphorus and less nitrogen) in the fall to assist flower bud initiation. I can't manage to keep up with that kind of schedule (well, I do have lots of plants) and if they get fertilized a few times a year they're lucky. I always dunk the pots in fertilizer water when I move them out in the spring and again when they come back inside in fall, and occasionally in between. Maybe I should fertilize more, but the plants grow vigorously and most bloom well, so I don't feel a real need to do more. As with watering, if you're unsure, less is better than too much.

So what kind of orchid should you get? First you should determine what conditions you can provide for your plant, primarily in terms of light and temperature. Here are some of the more common types that are good choices for orchid newbies:

• The "Moth Orchid," Phalaenopsis does well with low light intensity and prefers warm temperatures. A tall flower stalk emeges from the flat, glossy leaves, and produces a number of flat, often pink or white flowers, that can last for months. (Photo to the right)

• Cymbidiums need high light intensity, but cool temperatures to bloom. They are rather attractive plants with grassy foliage and tall, arching sprays of long-lasting waxy flowers in subdued colors.

• Cattleya types tolerate a wide range of conditions, preferring medium to high light intensity and intermediate temperatures. They are the most widely grown type and the one most growers start with. Numerous species and hybrids are available, with flowers in a range of sizes and colors, some of which are delightfully fragrant.

• Dendrobiums vary considerably in size and how the flowers are produced. Some  types have erect or arching sprays of flowers, while others bear clusters of flowers at the nodes along the stalks. Some are deciduous, losing their leaves after the first year. The different types require slightly different conditions, but most do well under the conditions for Cattleyas.

But don't feel a need to stick to these suggestions if something else has captured your fancy. My first orchid was an Oncidium splendidum that my husband gave me for Valentine's Day over ten years ago. It's bloomed reliably ever since, while some of the standard "easy" types have not. It produces a spectacular show in the dead of winter, with clouds of three-inch flowers of pure yellow with little bits of brown on 2-3 foot stalks.

Once you succumb and buy your first orchid, you're going to want to learn more about orchid species and care than is covered here. The American Orchid Society's Beginner's Library lists numerous books appropriate for the novice grower. Talk to other people who grow orchids and the vendors who sell them. But remember that everybody's conditions are unique and what works for one person may not work for you; even the types of orchids you can successfully grow may be different from your friends' on the other side of town.