There are many plant families with succulents in them, but two of these stand head and shoulders above the rest in terms of the number of species they contain — the Cactus family and the Ice Plant family.
Some other plant families have a few succulents together with many non-succulents, but these two are almost completely devoted to the art of storing water in their stems or leaves, which is what being a succulent is all about.The two families have differing geographical occurrences. The Cactus family is confined to the Americas while the Ice Plant family is heavily concentrated in Southern Africa.
Many kinds of cactus are commonly grown in California gardens, but only a few of the ice plants are carried in nurseries. This is a shame because there are so many unique and wonderful kinds.
A significant number of these are from the Western part of South Africa, which has a Mediterranean climate much like ours in California, with a mild winter rainy season and dry summers. At the Ruth Bancroft Garden, we have been trying out many of these winter-rainfall ice plants to see how well they do under our conditions.
One of the groups we have had success with is Cheiridopsis, a genus of 33 species that come from South Africa’s west coast and also the southwestern corner of neighboring Namibia.
These clump-forming plants are never more than a few inches high, with leaves that vary from long and narrow to short and chubby. They tend to bloom during the winter months, with delightful, brightly colored flowers.
Yellow is the most common color, but there are a few species with red or purple-pink flowers as well. Two of these have proved to be wonderful additions to the Ruth Bancroft Garden.
Cheiridopsis speciosa has pale gray-green wedge-shaped leaves that are up to a little more than an inch long, and its flower color varies from red-orange to purplish-red.
Cheiridopsis purpurea has leaves a little more rounded and fingerlike, with bright purplish-pink flowers. Both plants flower in winter, mostly in December through February, and their vivid blooms at this time of the year are most welcome.
As with many of their relatives, the flowers wait until the middle of the day to open, and then close up again in the late afternoon.
Even when not in flower, Cheiridopsis speciosa and C. purpurea have great visual appeal because of their compact clusters of highly succulent pallid leaves. Because they both come from the arid northwestern corner of South Africa, where the annual precipitation is less than half of ours, excellent drainage is a key part of growing them successfully.
They need plenty of sun, so tucking them between rocks with a south or southwest exposure is ideal. If not grown in a sufficiently sunny position, the clumps become less compact. They also are vulnerable to rot during periods of persistent rainfall.
Both species can take winter temperatures down into the upper 20s.
Brian Kemble is curator at the Ruth Bancroft Garden in Walnut Creek. His monthly column focuses on drought tolerant plants and dry gardens. Email questions to firstname.lastname@example.org. Learn more about the Ruth Bancroft Garden at www.ruthbancroftgarden.org.
Published at Thu, 16 Feb 2017 22:00:45 +0000