The Gasteria Page

The 16 species of Gasteria are native to Southern Africa. Their leaves range from an inch to over a foot in length. Leaves are produced in a linear array (distichous), but plants may become rosulate with age. The usually flattish leaves have a waxy surface, which may be attractively banded, furnished with white spots or warty. Leaves of the most fleshy species can be quite brittle. A few species have large triangular leaves. Leaf margins are smooth and may be acute or rounded, usually with an acute tip.
 
Gasterias are popular undemanding indoor plants, tolerating a little shade and infrequent watering. However, some sun ensures a compact growth habit, attractive leaf colouration in some species and abundant flowers. It is a mistake to allow these attractive plants to languish under the staging. The racemes of decorative pink to red flowers produce a good show in the Spring and intermittently throughout the summer. The individual tubular flowers have a distinctive basal bulbosity. The exact shape varies between species and divides the plants into taxonomic groups.
 
Gasterias seem resistant to most pests, but may be treated prophylactically with systemic insecticides based on Imidacloprid. Leaves are prone to unsightly black spots, which may be discouraged by avoiding humidity and condensation. The black spots will not spread and are the result of the plant sealing off damage or fungal infection with phenolic substances, which oxidise to a dark colour.
 
Single leaves or even a broken part, placed with the basal end touching damp compost will root and produce a whole plant. This takes time but can be useful to resurrect a damaged plant.

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