|Bulbine bruynsii, greenhouse-grown in Connecticut, January.|
Bulbine is a genus of about 80 species in the family Xanthorrhoeaceae (which, as currently circumscribed, also includes aloes and Haworthia). Bulbines are a varied assemblage, including geophytic species, weedy annuals and a few small shrubs. The arid, winter-rainfall climatic zones of South Africa and Namibia are home to numerous tuberous species of Bulbine with succulent leaves; some of these are window plants or form haworthia-like rosettes, though surely the strangest and most horticulturally intriguing species is Bulbine bruynsii.
|Bulbine bruynsii in flower, mid-winter.|
In its native habitat, B. bruynsii is confined to a small range on the edge of the coastal plain west of Bitterfontein, South Africa, where it grows in open areas among larger succulents and scrubby vegetation. In cultivation, it seems to be unfortunately finicky, requiring a cool winter growth period with very high light intensity, on the edge of what it is possible for me to provide in New England, even with a sunny greenhouse. Root rot is a problem, especially during the summer dormancy. A loose, completely mineral soil with lots of sharp sand, pumice and perlite seems to be beneficial.
Plants do form clumps from root-borne sprouts, but this takes years, so seed is probably the most practical method of propagation. The seeds are reluctant to sprout, though, much more so than with other bulbines that I have grown. Seeds sometimes germinate in old pots, a year or more after sowing, which suggests that the seed coat might need to be broken down. The next time I have some seed, I'll try lightly scarifying it by rubbing it around the palm of my hand with a little sand. One further complication: B. bruynsii is not self-fertile, so cross pollinating two different individuals is required for seed production.
|Bulbine diphylla, material from east of Bitterfontein, Western Cape Province, RSA.|
|Bulbine dactylopsoides, cultivated material via Lifestyle Seeds.|