Orchid Care: Watering, Lighting, Fertilizer, Repotting, and After Flowering

In their native habitats, orchids grow like weeds, but they are inclined to homesickness as houseplants. For the best results, provide the conditions they prefer. Some species have individual care preferences, but all need a balance of light, air, water, food, rest, and, from time to time, a new pot in order to thrive.

Lighting

• Without adequate light, expect lush growth but no flowers. Insufficient light is the most common reason for failure to bloom.
• These plants thrive in strong light, but direct sunlight can burn orchids. Bright, indirect light from an eastern or southern window is ideal.
• Leaf color is a good indicator of the amount of light an orchid is getting:
  • Bright green leaves indicate a happy, healthy plant.
  • Dark green leaves signal that a plant is not getting enough light.
  • Yellowish-green or red leaves indicate that a plant is getting too much light.
• If you suspect that your orchid is exposed to too much light, feel the leaves. If they feel noticeably warmer than the surrounding air, move the plant to a location with less intense brightness.

Air Circulation

• Orchids must also have fresh, circulating air. In the wild, continual gentle breezes are vital for their survival.
• Air in motion helps to evaporate stagnant water, which is a breeding ground for fungi and bacteria that are trapped during watering.
• Ventilation also helps orchids to tolerate intense light that would otherwise burn the leaves.
• Open windows in the summer and use an oscillating fan in winter. Without ventilation, orchids may eventually die from rot, lack of carbon dioxide, or disease.

Watering

• In general, douse plants early in the day with tepid water once a week in winter and twice a week in warmer weather. Water until the water runs out of the pot freely; this also flushes out any naturally occurring salts.
• Do not water orchids with ice cubes! Most orchid houseplants are tropical species and will not appreciate the direct chill of an ice cube.
• To know when to water, pick up the potted orchid and examine it: Is the potting mix dry? Does the pot feel light? This means that it probably needs a drink.
• Another way to tell if an orchid needs care is to look at its roots:
  • Plump white roots indicate a healthy orchid that’s being watered correctly. When watered, healthy roots should turn bright green.
  • Shriveled gray roots signal that the orchid needs more water.
  • Shriveled or spongy brown and black roots are a sign of rot, so cut down on watering.
• When indoor air is dry, spray orchids with tepid water to keep the humidity up. Terrestrials prefer to be kept slightly more damp than epiphytes.

Fertilizing

• As a general rule, fertilize orchids every two weeks during peak growth (spring and summer) and once a month during dormancy (fall and winter).
• Use a 30-10-10 fertilizer or orchid food, diluted to half strength.
• Approaching bloom, play it safe with a balanced fertilizer, such as 20-20-20.
• As a general rule, good orchid care includes fertilizing “weekly, weakly.”

Dormancy

• Many orchids need a period of dormancy—or rest—generally in winter. During this time, when you should reduce or stop fertilizing, plants strengthen their root systems, grow leaves, and stockpile energy for their next growth spurt and bloom. Typically, an orchid can rebloom every 8 to 12 months.

Repotting

• When an orchid spills out of its pot, the roots trail down the sides of the pot, or the growing medium is reduced to crumbs, it’s time for repotting.
• Repot at the beginning of the next growth cycle (typically in the spring).
• Do not repot while a plant is flowering, as the blooms may suffer. Enjoy the flowers, then cut off the spent flower spike with sterile snippers and repot the orchid.
• Orchids should be so snug in their pots that you can pick up the plant by its leaves and not shake out the roots.
• Orchid potting mixes are made of fine, medium, or coarse fir bark chunks, which are usually combined with perlite, peat, or sphagnum moss, and horticultural charcoal. (You can mix up your own, using four to six parts bark to one part each of the other components.)