Tillandsias as Houseplants
Figure 1. Tillandsias are easy care houseplants if you understand how they grow in their natural environment. Holly Thorpe, Penn State
Tillandsia, commonly known as air plants, comprise the largest genus of the bromeliad family (Bromeliaceae), with about 660 species. Fellow bromeliads include an array of colorful tropical plants, including orchids, Spanish moss, and pineapples. Air plants are epiphytes, meaning they attach to other plants or rocky substrates as a means of support. Their roots are used solely for attachment - rather than absorbing nutrients or water via roots. Air plants rely on the moisture in the atmosphere to grow and thrive.
While tillandsias bloom, their most striking feature is their leaves. The leaves are the plant's photosynthetic centers and absorb water and nutrients through their trichomes. Trichomes are specialized structures on the leaves of air plants that trap moisture and dust. Initially, trichomes look like fuzzy hairs, but they are actually modified scales, which are cup-shaped. The more prominent the trichomes (denser and fuzzier) are on an air plant, the better adapted it is to arid climates because they can collect more water and nutrients.
Air plants are divided into two categories: mesic (meaning "middle") and xeric (meaning "dry"). Mesic air plant species hail from moderately humid regions such as South American rainforests. They thrive in a canopy of trees and prefer more filtered light than their xeric counterparts. The leaves of mesic types are slightly cupped, deeper green, smoother, and have smaller trichomes. Xeric air plant species are from desert-like climates and are often rock dwellers. Their leaves have more significant numbers of trichomes, resulting in a gray or fuzzy appearance. Often, their leaves are wider to allow a larger surface area to absorb water and light.
Tillandsias are forgiving indoor plants if given adequate amounts of light and water. They do best with bright, indirect light, preferably in an east or west-facing window. In our region, which has a number of cloudy days, excessive sunlight is unlikely to cause the demise of an air plant. Air plants will make a great addition to the outdoors during the summer. To prevent scorching, keep them in shaded areas, such as under landscape trees. Like most houseplants, air plants prefer nighttime temperatures above 55°F and daytime temperatures between 65°F and 90°F.
Misting, rinsing, or soaking are three methods of watering tillandsias. Misting air plants to the point of run-off may have to be done every other day with low household humidity. Rinsing may be the simplest watering technique. Gather the air plants twice a week, hold them under the faucet, and rinse them thoroughly with tepid water. Lay them face down on a paper towel for a few seconds to drain off excess water. Other sources report great success by submerging air plants weekly for 20 minutes to an hour and draining them well. Good air circulation is essential to air plants. While they look great enclosed in glass, be sure to allow plants to dry at least four hours after watering before placing them back in a terrarium. Avoid air conditioners and heating vents, which can quickly dry out the air plants.
Air plants bloom, but only once in their lifetime. The flowers come in many shapes and various colors, from coral to pinks and purples. Tillandsia spp. will set seed after flowering. The seeds are attached to fluffy tufts called coma and drift on air currents. To encourage air plants to bloom, provide them with the maximum allowable light, sufficient water, and fertilizer. Some species, such as T. crocata, have fragrant blooms reminiscent of jasmine or gardenia.
The primary propagation method of air plants is the production of "pups" or small offsets. These are new plants emerging from the base of the mother plant after the plant flowers. Once pups are one-third the size of the mother plant, they can be gently separated from the main plant and grown on their own, or they can be left in place, allowing the plant to form a clump.
Tillandsias benefit from a monthly application of fertilizer formulated for bromeliads or orchids. A fertilizer higher in nitrogen helps promote foliar growth. Clemson University Extension recommends diluting liquid fertilizer to one-fourth the recommended rate and adding it monthly to the regular watering regime.
The fact that air plants thrive without the encumbrance of soil offers lots of options for their use in decorating. Many air plant displays take advantage of this by suspending the plants on a wire, hanging them on walls, dangling their leaves from shells, or simply plucking them into vases or pretty much anywhere they look interesting.
Most air plant displays feature them in contemporary settings with organic elements such as rocks, shells, and driftwood. Try an updated spin on wreaths by adding moss and air plants to a grapevine wreath. A vintage vase with a single T. xerographica tucked inside looks fun and fresh. If you have a tall houseplant such as a cactus or amaryllis, cover the potting soil with pebbles or moss and place some tiny air plants at their feet for added foliage interest. It's easy to gather them up once a week, rinse them off, and play with fresh placement without a speck of dirt to clean up afterward.
