There are more than 650 types of air plants (Tillandsia spp.) that can grow—and thrive—without soil. This plant is almost unkillable, so it's perfect for gardeners who tend to have a "black thumb."
Air plants grow without dirt and come in all sizes and colors. Allthough air plants used to be a rare greenery, these hardy plants have become popular in the past couple years, so you can find them at almost any garden center—or even in the check-out line at the grocery store. There are also a number of online nurseries specializing in air plants.
Many air plants grow with strap-shape or slender triangle-shape leaves, and most have attractive tubular or funnel-shape flowers.
Air plants are epiphytes, meaning plants that grow without dirt. Air plants attach themselves to rocks, trees, shrubs, or the ground with their roots and are native to the southern United States, Mexico, Central America, and South America.
There are several types of air plants: Those with silver foliage tend to be the most drought-tolerant; greener plants dry out faster.
The key to air plant survival is constant air circulation, as its name indicates. Water your plants about once a week—some varieties can go two weeks without being watered. Keep an eye on them to determine what exactly your plant needs. To water, place them in the sink and lightly rinse each plant. Leave the plant in the sink overnight to drain; put them back in their designated place in the morning.
If one of your plants looks severely dried out, pull off the bottom dried parts and place the plant in a bowl of water for several hours. In the winter, if your home's heater is on, your air plants may look a little dry. Simply mist them with water (concentrating on the base of the plant) every few days to keep them looking fresh.
Although they love warm weather, most air plants need protection from full sun. If it's a type that grows naturally wild on trees, keep it in moist, partial shade. If it is a ground type, such as T. cyanea or T. lindenii, grow it indoors in bright, filtered light or outdoors in partial or dappled shade.
Don't let an air plant sit somewhere colder than 45 degrees; it will die at those temperatures. If you live in Zone 9 or warmer, you can grow an air plant outdoors all year if you keep it dry during the winter.
You'll know that an air plant is happy when it sends up flowers. Once the flower dries out, all you need to do is snip it off.
Air plants look great alone as architectural elements or in an air plant terrarium. Place varieties such as Tillandsia aeranthos 'Amethyst', also called the rosy air plant, in a pot or against a container that complements or contrasts its pink flower spike.
Play off the spikiness of the foliage by grouping three Tillandsia ionantha and add a tiny toucan, parasol, or other tropical touch.
Air plants naturally suited to growing in trees can be lashed against a protected wooden post with translucent fishing monofilament and a bit of sphagnum moss to hold moisture. Tillandsia species also make fine companions on a branch with orchids because they like essentially the same conditions. Hanging air plants are a popular design element.