|
Eulophia
is a very large pantropical genus and is represented in southern Africa
by 42 species. The plants grow terrestrially in small to large colonies
in grassland, marshes, savanna and scrub, and occasionally also in fynbos.
With their open, and often also fairly large flowers in brilliant colours,
they resemble 'typical orchids' more than other indigenous South African
orchids. Flowering occurs in spring or summer.
Plants have underground corms or partly aerial pseudobulbs. Leaves, which
may be absent or present at the flowering time, are either thin-tissued
or leathery (sometimes even succulent). The erect inflorescences are always
lateral and bear a number of medium-sized or large flowers. In most species
these are resupinate (lip facing down). Sepals and petals are normally
simple and always unspurred. The lip is most commonly three-lobed and
usually has a basal sac or spur. On its upper surface it has various outgrowths
like crests, papillae or lamellae, but a large lip appendage as in Pterygodium
is not present. The column is stout to elongate and has a prominent undifferentiated
column-part. Apically it bears the anther (pollen sac) which is positioned
under a 'lid' called the anther cap. The stigma is situated in a cavity
on the front side of the column below the anther.
Cultivation
Plants of this genus are frequently cultivated as they are not very
difficult to grow in sandy soil in pots, and are also attractive with
their medium-sized to large flowers in brilliant colours. They are best
grown together with bulbous plants as these have similar cultivation requirements.
Specialist bulb nurseries sometimes offer plants of this genus.
Eulophia corms should be planted in a well drained medium in a
deep pot (20-30 cm deep) under 40 % shade. A suitable medium would be
70 % river sand and 30 % milled pine bark or well-decomposed compost.
Additionally some compost or leaf mould can be placed in the base of the
pot and the rest of the medium on top. Most of the cultivated eulophias
are from the summer-rainfall region and are dormant during the winter
period. The plants should thus be treated like bulbs and kept on the drier
side during the winter season, commencing with watering only once the
new shoots appear. Watering in the summer period can be done once or twice
a week depending on dehydration rate of the medium. Feeding is only done
during the summer growth season. Fertilizers that have been used successfully
are: Nutrisol, Nitrisol, Seagro, Multifeed 10, Osmocote and Horticote.
Pests to watch for are aphids and red spider.
Selected species and their main distribution
Winter-rainfall area: E. litoralis, E. tabularis
Summer-rainfall area: E. macowanii ('cream flag orchid'),
E. clavicornis, E. ovalis, E. zeyheriana, E. streptopetala, E. speciosa,
E. cucullata, E. horsfallii ('purple vlei orchid'), E. angolensis
('vlei orchid'), E. petersii, E. welwitschii, E. foliosa, E. leontoglossa
('lion's tongue')
Both areas: E. aculeata ('aandblommetjie')
|