Tillandsia February 23, 1998 Tillandsia is the largest and most widely distributed genus of Bromeliads, with over 400 species from South America to Mexico. Almost all have rosettes of leaves, which must be attached to bark or branches (epiphytes). They can vary from 6 cm to 4 m in height. Tillandsia plants are herbaceous with silver-grey to green leaves and like warm humid air and sunlight. They can have flowers in the middle, but have few roots. Common air plants are Tillandsias that grow on bark, but my Tillandsias are fancier species grown on driftwood.