Julian Slade
Sun, 06 Jul 2003 23:06:49 PDT
Albuca is a genus of 60 to 70 species belonging to the Hyacinthaceae family,
to be precise in the subfamily Ornithogaloideae. It is apparently most
closely related to Ornithogalum subgenus Osmyne (alternatively treated as
genus Coilonox).

All Albuca species grow from bulbs, and most have a dormancy period after
flowering whereby they lose their leaves. The flower scape is, like almost
all Hyacinthaceae, unbranched. Most species only produce one scape per
growing season, although some, such as A. flaccida and A. maxima, may
produce two or more; the tropical African species may produce scape after
scape after scape in optimal conditions. The majority of species are
winter-growers, mainly originating from the south-west Cape and northwards
into Namaqualand, South Africa. The genus also extends into tropical Africa
and Arabia, where there are comparatively fewer species.

The most characteristic feature of the genus is the shape of the flower. The
outer 3 tepals spread out like any normal flower, but the inner 3 stay more
or less closed. The general appearance is therefore somewhat like a snowdrop
(Galanthus). The flowers do come in a limited color range, white and yellow
through to green, but are usually embellished with a green stripe down the
middle of each outer tepal. Some species also have the tips of the inner,
closed tepals colored differently, either with white or bright yellow.
Flowers are either presented in a nodding or drooping formation, or erect on
firm pedicels (flowerstalks). The tropical African species, on the other
hand, have flowers on such short pedicels that the only position they can
hold is sideways.

Another interesting floral feature lies in the anthers (pollen sacs). In
most species, three alternate anthers are noticeably different. They can be
slightly shorter but otherwise similar to the other three, or much smaller
with limited if any pollen, through to minute remnants or even non-existent.
This feature is consistent within each species.

Flowers of many species, mainly the white-flowered ones, lack scent, but
many of the yellow- to green-flowered species have rich, pleasant perfumes,
always difficult to describe precisely.

Based on the structure of the flowers, the genus can be subdivided into 4
Subgenus Pallastema has long and slender styles, and stamens that are
arranged zygomorphically (much like in Lachenalia). The inner tepals tend to
be slightly outspread, and the outer tepals not opening as wide as in the
other subgenera. This subgenus is tropical African.
The other subgenera have thick styles, and stamens arranged
actinomorphically (like in Scilla) but bunched close together due to the
inner tepals being held more or less shut. Their distribution is biased
towards the winter-rainfall area of South Africa, especially the western
part. They are distinguished from each other solely in the structure of the
tips of the inner tepals: subgenus Albuca has thickened tips attached by a
narrowed hinge; subgenus Mitrotepalum has thin hooded tips; and subgenus
Falconera has thickened but unhinged tips.
Knowing which subgenus a plant belongs to is the only way one can begin to
correctly identify it!

Although there is not a great diversity in the shape of the flowers, there
is however a fascinating range of leaf form. Some species do admittedly have
rather uninteresting foliage, others have such unusual leaves that they
could be grown as a foliage plant in their own right. Leaves can be
boat-shaped, coiled into corkscrew shapes, or narrow and wavy like a
slithering snake. Even some of the otherwise uninteresting species have
unusual ornamentation on their leaves, the most frequent being numerous,
small glands. These glands are like stubble with sticky tips, resulting in
the leaves attracting dust and dirt, the occasional small insect and, in
gardens, lint and hair!

Some of the most noteworthy species are described below:

Albuca abyssinica
A member of subgenus Pallastema. Flowers yellowish with some green.
Flowering any time of the year, particularly in summer. Evergreen to
winter-deciduous. Several species, such as A. angolensis and A. melleri, are
now considered part of this species.

Albuca clanwilliamigloria
A member of subgenus Falconera. Flowers drooping, golden yellow, almost
orange! Plants very tall, at around 6-7 feet (2 m). Bulb sometimes produces
small bulblets. Flowering late winter to spring. Winter-growing,

Albuca flaccida
A member of subgenus Albuca. Known for many years as A. canadensis -
thankfully this absurd name has now been disallowed! Flowers yellowish
green, nodding, strongly and pleasantly perfumed. Flowering late winter and
spring. Winter-growing, summer-dormant. This species produces copious seed
which is easily dispersed by the wind, and has become naturalized in
south-western Australia.

Albuca hallii
A member of subgenus Albuca. Leaves corkscrew-shaped, glandular. Flowers
nodding, yellowish. A dwarf species, growing to only 4-6 inches (10-15 cm)
tall. Unique among the winter-growers in flowering in autumn, often before
the leaves have fully developed. Not in cultivation (yet!).

Albuca humilis
A member of subgenus Mitrotepalum. Flowers white with a green stripe which
ages to brown, only 1 or 2 in number. Leaves few, very narrow. As its name
implies, a dwarf plant, only about 4 inches (10 cm) high.
Summer-growing/flowering, winter-dormant. May be cold-hardy.

Albuca jacquinii
A member of subgenus Falconera. Supposedly a 'form' of A. viscosa. Leaves
narrow, glandular, corkscrewed at their tips, otherwise straight. Flowers
bright yellow with a green stripe, nodding, rather dainty, strongly and
sweetly perfumed. Flower scape quite slender, also glandular. Grows to about
12 inches (30 cm) or more tall. Flowering late winter and early spring.
Winter-growing, summer dormant. Has unusually small seeds for an Albuca.

Albuca maxima
A member of subgenus Albuca. Flowers white with a green stripe, nodding or
drooping. Leaves somewhat succulent and rigid, deeply channeled, covered
with a gray powdery bloom. Quite tall, 5-6 feet (1.5-1.8 m). Flowering late
winter and spring. Winter-growing, with a very short summer dormancy. This
species also produces copious seed, and has reportedly become naturalized in
Italy. Formerly known as A. altissima.

Albuca nelsonii
A member of subgenus Mitrotepalum. Flowers erect, white with a green stripe
that becomes reddish-brown with age. Leaves evergreen, bright green,
narrowly triangular, numerous. Bulb partially exposed above ground,
multiplying rapidly. About 3-4 feet (90-120 cm) high. Flowering late spring
and early summer. Sometimes incorrectly distributed as A. altissima.

Albuca pendula
A member of subgenus Pallastema. Flowers yellow-green. Notable in having
extremely long (to 6 feet / 2 m), fairly broad, floppy leaves. In its native
Arabia it grows on cliff faces, where its leaves can dangle freely.

Albuca shawii
A member of subgenus Falconera. Flowers yellow and green, nodding. Leaves
narrow, glandular, reputedly smelling of aniseed when crushed!
Summer-growing/flowering, winter dormant. A. trichophylla is synonymous.

Albuca spiralis
A member of subgenus Albuca. Flowers green with pale yellow margins,
nodding. Sweetly scented, reportedly of butter and vanilla! Leaves narrow
and glandular, wavy like a snake to spirally twisted. Flowering late winter
to mid-spring. Winter-growing, summer-dormant.

The winter-growing species are cultivated like any other Cape bulb, often
with greater ease. Although Albuca maxima does appear to tolerate summer
watering it, like all the winter-growing species, fare better kept dry but
not hot in summer.

Because most species rarely produce offsets, growing from seed is the best
way to increase stocks, and is usually the only way to obtain most species.
All species, however, are extremely easily raised from seed, sown at about
the same time adult plants come into active growth. Fresh seed often
germinate within a week of sowing, often with 100% germination. Seedlings
usually flower in their third year.

Julian Slade

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