SA Orchids: Stenoglottis

S. longifoliaStenoglottis is a small African genus distributed from the Eastern Cape to Tanzania. All 5 species are represented in South Africa. The plants grow singly or in groups on the forest floor of both high altitude and coastal forests, and are fairly common in some locations. They thrive mainly on rocks (epilithic) but sometimes also as low-level epiphytes on tree trunks. Occasionally the plants grow terrestrially in soil. Flowering occurs in spring or summer.

The plants have several cylindrical root tubers and basal rosettes of narrowly lanceolate (lance-shaped) leaves. Leaves are often undulate (wavy) on their margins and variously purple-dotted on the blade. The resupinate flowers are medium-sized and white to pink in colour. Their most prominent organ is the lip which is deeply three- or five-lobed. In most species it lacks a spur. The four currently recognized species are very variable in most of their characters, and after further study of the entire genus it will probably become necessary to recognize more than the four species.


Cultivation


In cultivation Stenoglottis fimbriata and S. longifolia are probably the easiest South African orchids. Plants are also fairly easy to obtain - nurseries regularly sell potted plants.

Plants are best grown in deep pots (e.g. 20 cm depth, place tubers at 10 cm depth) in a well drained medium consisting of 50 % river sand, 40 % leaf mulch and 10 % vermiculite. Plants are best grown in a temperate environment with 50-70 % shading and excellent ventilation.

Regular watering should be given during the growth season, i.e., from spring to autumn. As soon as autumn cooling sets in reduce watering to once every two weeks. During cold winter months do not water. It is however vital to watch that the medium does not dehydrate completely. To prevent this, drench pot occasionally and allow to dry. Do not keep the medium damp. Only once the new shoots emerge at the end of winter commence with watering once every two weeks for the spring season and once or twice a week as required for the summer season. A slow release fertiliser such as Osmocote can be applied during spring. Pests to watch for are aphids.


Selected species
S. fimbriata ('fringed stenoglottis') (shown below), S. longifolia (shown above)


Description and images : Hubert Kurzweil
Cultivation: Hildegard Crous
October 2000
(Updated by Clare Archer, August 2010)


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