Growing Orchids

Light Requirements of Orchids

Orchids are fairly hardy and can survive in a variety of conditions, but the light requirements of orchids are an important consideration because light is very important for orchids' flowering. And, because there is a lot of sunlight at tree tops, epiphytic orchids and orchids with pseudobulbs usually need more light than terrestrial orchids or those with soft leaf growth.

While it may take an orchid plant three to eight years before it is mature enough to bloom, some orchids will sit around fat and green for years and never flower until they get enough light. In contrast, when the plants start to shrivel and get yellow, the light is too strong. When growing orchids in a window, resist the temptation to crowd the plants together. Keep them far enough apart to make sure that each plant gets its share of the light. Turn the plants from time to time so the whole plant gets the benefit of the light.

When growing orchids outside or in a greenhouse, orchids may need shade in the summertime to protect them more from heat than from the light. This is done outdoors by growing them under trees or in a lathhouse. In a greenhouse this can be done by using blinds inside or out, by using mesh, or by painting shading compound on the glass.

These indoor orchids are blooming beautifully because the light requirements of orchids are being met.
These indoor orchids are blooming beautifully
because they are receiving the proper
light requirements.

When there is not enough natural light, orchids can grow and flower under artificial light. The smaller, compact plants are easier to handle. Some orchids can take as long as two years to adjust to growing under artificial light but, when they do, they often bloom more frequently. In addition, high artificial light intensity can speed up the growth of seedlings.

With orchids, a mixture of fluorescent and incandescent light seems to work better than fluorescent light alone. A proportion of five watts of cool white and daylight fluorescent light to one watt of incandescent light works well. Because of the heat generated by the standard 25 watt (120 volt) incandescent bulbs, 25 watt (130 volt) extended service bulbs are often used. They are cooler and last twice as long. Use the longest fluorescent tubes available that will fit your growing area; the light intensity always falls off at the ends of the tubes.

Not all orchids are affected by seasonal changes in day lengths, and many orchid growers keep their lights on 14 hours a day. However, timers are a must if you are growing a lot of plants indoors and under lights.

Water is another essential for every type of plant, so orchids are no exception. On the next page, learn how to water your orchids appropriately.

Check these resources to find more ideas and information on placing plants around your house:

  • Gardening: Whether it's vegetables, flowers, or foliage you're considering, the facts you'll need are here. Learn all the basics of successful gardening.
  • House Plants: Wondering what might look nice in your kitchen window? Find out which plants are happiest inside the house.