Tillandsia, or air plants, are members of the Bromeliad family of plants that absorb water and nutrients through their leaves. They are epiphytes, meaning they grow attached to other plants, not in soil. They are not parasites; they do not harm their host. They are fascinating plants, often with colorful blooms. They are not difficult to grow.
Tillandsia can tolerate temperatures from freezing to above 100 degrees Fahrenheit, but they do best at temperatures from 50 to 90 degrees Fahrenheit.
Tillandsia should receive bright but filtered light from April through October. Many varieties will get sunburned if you leave them in direct sunlight during the summer. They are well suited to a greenhouse or a shaded patio that is protected from frost. Put them within 3 feet of a window with bright light.
Plants with green or light-green leaves like shady conditions. Plants with thick, stiff, gray or white leaves need more light; they naturally grow in full sun and can tolerate full sun in humid areas.
If you're growing Tillandsia indoors, place them from 6 to 36 inches from full-spectrum fluorescent tubes. A 48-inch fixture with four tubes works well. Set a timer for 12 hours a day.
How often you water your air plants depends on the size and variety of the plant and the circulation of air, but two to three times per week is usually best.
Drench your air plants until they are thoroughly wet. If they are indoors, use a watering can or sink hose. Plants should receive enough circulating air to dry within four hours after you water them. If you need more air to dry them, use a fan.
If you live in a hot, dry climate, water them more often; if you live in a cool, humid climate, water them less. If you live in a dry climate you may spray mist them to increase humidity between regular waterings.
Do not let your Tillandsia stand in water. If you are not watering them enough, the natural concave of their leaves will increase.
Use a 17-8-22 Bromeliad fertilizer twice a month. If Bromeliad fertilizer is not available, use other water-soluble fertilizers at 1/4 strength. Epiphyte elixir or orchid fertilizer also works. If you just received a plant from a nursery, do not fertilize it for at least three weeks.
If your air plant begins to rot from the center, slowly remove the center leaves one at a time until they get hard to pull. Treat the plant with a fungicide that is not copper-based. Keep it slightly drier to avoid more rotting.