Tillandsia bulbosa aka Bulbous Airplant

Tillandsia bulbosa, the bulbous air plant, belongs to the bromeliad family. It comes from tropical America, where it grows in wet tropical climates. This evergreen perennial grows as an epiphyte, rather than in soil. It forms clumps and keeps its green leaves year-round. In Britain, it suits growing under glass, with summer spells outdoors.

Plants are often about 0.5 feet [0.15 metres] tall and wide. The RHS lists a broader size range reaching 1.6 feet [0.5 metres] in both directions. Its swollen base can reach 0.16 feet [0.05 metres] across. Narrow green leaves rise from this base and twist. Their edges roll inward, giving each leaf a tube-like shape. The RHS gives a maturity period of five to ten years.

At flowering, the upper leaves turn shades of scarlet. Bright violet-purple flowers grow on short red stems. The flowers have a tubular shape that contrasts with the curled leaves. Individual rosettes die after flowering, and these can be removed. Plants can grow from seed or from detached offsets. Wait until offsets reach one-third of the parent's size before separating them.

Grow this air plant without compost, fixed to a support. Glue or wire can hold it in place. Give it bright, filtered light and good air flow. The RHS recommends growing it under glass in partial shade. From spring through autumn, immerse it in rainwater twice weekly. Increase watering when conditions turn hot and dry. Drain it well after each soak, then let it dry. It can spend summer outside for rain, light, and humidity. Choose a sheltered spot rather than an exposed site. Its RHS hardiness rating is H1C. This allows summer outdoor growing at 41–50°F [5–10°C].

Its small size suits supported displays in greenhouses or conservatories. The RHS also lists patio and container uses. Its curled leaves provide interest even when flowers are absent. At flowering, red foliage and purple blooms add strong colour. No soil bed is needed for a mounted display. Aphids and mealybugs may attack plants, so check for them. The RHS reports few disease problems for this species. The supplied evidence gives no information on edible parts or toxicity.