A Cape hyacinth with flowers and scent to rival any European hyacinth.
Like all other Lachenalia species, L. fistulosa is a typical winter-growing bulb that is summer-deciduous, i.e. it becomes completely dormant during the hot dry summer months in the Mediterranean-type climate of the Western Cape.
The Cape hyacinth consists of a single white fleshy bulb, about 20–25 mm in diameter, covered by a multi-layered brown papery tunic, with fine white adventitious roots, and one or two strap-like lanceolate leaves 45–120 mm long. Lachenalia fistulosa does not have any bumps or pustules on the upper surface of the leaf as do some Lachenalia species. The leaves are leathery and usually bright green, occasionally covered with dark green, brown or magenta spots on their upper surface. The leaves will start to emerge a few weeks after the first rains in autumn, and then wither naturally in late spring/early summer .
The inflorescence, in the form of a spike, can grow up to 120 mm tall and appears in late spring (September to November in the southern hemisphere). Flowers are tubular, swollen at the base and somewhat constricted and then flaring distinctively at the mouth. The flower colour is variable. Plants on Lion's Head and Signal Hill tend to be pale cream or grey, while just a few kilometres away on the slopes below Devil's Peak they are light blue with lilac or pink tips. Other colour forms include yellow, white and violet. All flowers age to a dull red. The flowers are sessile (without a stalk).
The fruit are small capsules that ripen a month or two after flowering to release small shiny black seeds, which are shaken loose by wind action.
This species is not currently recognised as being threatened, however, some authors recommend a Red List status of vulnerable (VU) as its natural habitat is now very limited.
Distribution and habitat
Lachenalia fistulosa is restricted to the Cape Peninsula except for a disjunct late-flowering population at Miaspoort in the Du Toitskloof Mountains. It occurs in Hawequas Sandstone Fynbos, Granite Fynbos and Peninsula Shale Renosterveld vegetation types, preferring heavy stony shale or granite soils, sometimes occurring singly, but often in large stands.
Derivation of name and historical aspects
Its specific name fistulosa refers to the hollow formed by the tepals of the flower.
Lachenalia fistulosa has sweetly scented flowers and is pollinated by Cape honeybees ( Apis mellifera subsp . capensis ). Populations tend to flourish and flower profusely in the season after a veld fire as the removal of other vegetation results in them having optimal sunlight. As the height of surrounding vegetation increases, they tend to flower less and can sometimes remain completely dormant. This pioneering nature is evident in vast populations that flourish and flower in the frequently mowed roadsides along De Waal Drive, Cape Town.
Uses and cultural aspects
No ethnomedicinal uses are recorded for the Cape hyacinth. However, they make for stunning potted subjects in indigenous gardens.
Growing Lachenalia fistulosa
Lachenalia fistulosa is very easy to grow and a rewarding species to grow as a pot subject. The soil medium should be fairly well-drained and consist of about half coarse washed sand and half finely sieved compost. Use this mixture to fill the lower two thirds of the pot. The upper third should be pure sand (with no loam or compost) into which the bulbs are planted. This layer stays relatively dry, preventing the bulbs from rotting if they should get too wet, while the roots can safely penetrate the richer moister organic medium below. Place the pots in full sun where the plants will grow very happily outside during the winter months, providing the temperature does not drop below freezing. In summer, the bulbs should be kept dry, preferably in a cool position. One can either lift the bulbs and store them in paper bags or store them in their pots. They perform well if they are repotted every 2–3 years with fresh soil medium.
They are easily propagated by leaf cuttings, which can be removed from the plant by slicing them at the base of the leaf blade. Half bury these leaves in a very coarse free-draining sandy medium and leave them in a cool place out of direct sunlight. Keep the soil relatively dry to prevent the leaves from rotting, while keeping the humidity quite high—humid air and dry soil is the trick. Within a few months, small bulbils will appear along the cut edge at the base of the leaf. Eventually the leaf will wither but the bulbils can be planted like normal bulbs the following season. Flowering will take 1–2 years.
They are also easily raised from seed, which should be sown in autumn in a similar medium used for cultivation with a thin layer of sand placed over the seed. Water them gently but regularly in the first few weeks. The seedlings should germinate within about 2–3 weeks. Flowering will take 2–3 years.
Lachenalia fistulosa doesn't have many pests apart from snails and caterpillars (which can be removed by hand) and mealy bug which should be treated with a systemic pesticide. A rust fungus can be problematic and appears as orange blotches on the leaves, often developing where a leaf has been damaged by hail, for example. This is easily preventable (which is preferable) and treatable with common fungicides.
Not much fertilising is required for these bulbs, as they are not generally very demanding, but they would respond well to small doses of a diluted low-nitrogen liquid fertiliser.
References and further reading
- Duncan, G. 1988. The Lachenalia handbook . National Botanical Gardens, Kirstenbosch, Cape Town.
- Duncan, G. 2012. The genus Lachenalia . Royal Botanic Gardens, Kew.
- Mucina, L. & Rutherford, M.C. 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute. Pretoria.
- Raimondo, D., Von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. & Manyama, P.A. 2009. Red List of South African plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.
Kirstenbosch National Botanical Garden