Plant Highlight: Aloe vanbalenii
By Brian Kemble
Area of occurrence
South Africa has many species of Aloe that flower in winter, and one of these is Aloe vanbalenii, found in KwaZulu-Natal Province in the eastern part of the country. This is a stemless or short-stemmed species with spreading leaves that curl downward at the tips. Though plants are sometimes solitary, they usually form a multi-headed clump in time.
About the plant
The leaves of Aloe vanbalenii are up to 2½ feet long (80 cm) and up to 6 inches wide at the base (15 cm), tapering to a point at the tip, which often touches the ground because of the way the leaves curve downward. The leaves are strongly channeled, with small triangular teeth (to ⅕ inch long, or 5 mm) at intervals along the margins. In shadier positions, the leaves are green, but in bright sunlight they become red-tinged. In habitat, the species occurs in an area where rain in winter is a rarity, so plants with full sun exposure often turn completely red at the time of their flowering. This coloration is not achieved at the Ruth Bancroft Garden, but it can sometimes be seen in cultivated plants in the sunnier and drier parts of southern California (see accompanying photos of plants in San Diego County, California).
About the flowers
At the Ruth Bancroft Garden, Aloe vanbalenii typically begins flowering in January or early February, ending in late March or April. With the warmer winters in southern California, the flowering commences earlier and ends earlier. In the Southern Hemisphere home of A. vanbalenii, winter comes at the opposite time of year, and peak flowering is typically in June-July. A rosette may produce one to three inflorescences, rising to a height of 48 inches or so (1.25 m), and each of these may be single or with a side-branch or two. The stalk is slender, with a few papery bracts at widely spaced intervals, and the racemes (flower clusters) are narrowly conical, eventually becoming less pointed as they approach the end of flowering. The tubular flowers average about 1.4 inches in length (35 mm), and their color is variable. Often the buds are colored more darkly than the open flowers, yielding a two-tone effect, but this is more pronounced in some plants than others. A typical plant might have yellow-orange buds, lightening to pale yellow as the flowers open, but sometimes plants have deeper orange buds, or even red-orange or dull-red buds.
About the fruit & seeds
If successfully pollinated, a flower yields an erectly-held blimp-shaped capsule. Within are three chambers holding stacks of small brown seeds with papery margins. At maturity, the capsule dries and turns brown, and at this point it splits open to spill the seeds.
Click here to find out more about what’s in bloom at the Garden.