Air plants are epiphytes. They do not grow in soil but in trees or on rocks, anchored by root-like structures or stems. Air plants are not parasitic. They absorb the nutrients and moisture they need from the air or from crevices on the surface of the host through tiny, silver-colored, cupped scales called trichomes on the air plant's foliage. Spanish-moss, sky plant and ball moss are a few examples of this huge and varied species.

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Spanish moss plants can become so large and heavy that they damage their host tree by breaking branches or blocking sunlight.

Spanish Moss

Spanish moss (Tillandsia usneoides), also called Florida moss, long moss or graybeard, is not a type of moss. It is an epiphytic plant that grows on trees or just about anything it can attach itself to. The gray-green, 2 -inch long leaves cover 20-foot long stems that drape down from the host to blow in the breeze. Spanish moss grows naturally throughout Central and South America and the West Indies as well as the southeastern United States from Virginia to Florida and into Texas. It grows in warm, moist, partially shady garden areas, preferably on oak or cypress trees. Spanish moss also can be mounted on cork board or driftwood, placed outside for the warm summer months and brought into a heated area for the winter.

Sky Plant

The sky plant (Tillandsia ionantha), known also as blushing bride, is a tiny air plant that grows to 2 inches tall. This rare and endangered air plant grows naturally from Mexico into Nicaragua on trees and rocks at elevations of 2,000 to 5,500 feet. The plant is composed of grayish-green leaves that grow in rosette form. As the plant matures, the older foliage takes on a red/orange color. Sky plants produce bright blue or purple flowers in late fall or winter. They often are mounted on cork board, bark slabs or pieces of driftwood and grown in the home or greenhouse.

Ball Moss

Ball moss (Tillandsia recurvata), also referred to as bunch moss, grows in clumps 6 to 10 inches in diameter, with 2- to 6-inch long gray-green leaves. It blooms in the fall, producing a 6-inch long spike with between one and seven 1/2-inch pale blue to violet flowers. This air plant grows naturally in the southern United States from Arizona through Texas, Louisiana, Georgia and the Florida peninsula and south into Argentina. Live oak trees are this plant's preferred host, but it will grow on other hardwood trees or even on suspended telephone or electrical wires. It is most commonly found on dying or dead branches of trees. This plant also is grown as a houseplant, generally mounted on cork board, bark slabs or in a slatted basket.