the tender Mexican and Mediterranean species require occasional shading in summer or protection from frost; the others are hardy and self-sufficient almost anywhere the year round. All species are quickly and easily propagated cither by leaf or stem cuttings, or seeds or divisions.

The Sempervivum Tribe. The sixth and last tribe of the Cras-sula family, like the fifth, contains two distinct groups of succulent planLs— one hardy, the other tender. The hardy members are contained in the well-known genus of European alpine plants called Sempervivum (sem-per-vy'-vum), the tender one^ in several African genera related to it They are all rosette plants, somewhat reminiscent of the echeverias. yet distinct in the shape and texture of their leaves, their growing habits, and blooms.

The genus Sempervivum consists of about twenty-five species of small stemless, many-leaved rosettes native to ihe mountains of Central and Southern Europe. Although the individual plants are only one fourth inch to six inches in diameter, they produce innumerable offsets from their leaf axils which form clusters and eventually great mats, sometimes a yard or more in diameter. The starry pink, white, yellow, or purple flowers are borne in dense heads each summer, after which the flowering rosettes die. Although these hardy sem-pervivums, or Houseleeks, as they are popularly called, are perhaps of greater interest to the collector of rock-garden and alpine plants, they have much to offer the succulent enthusiast as well. In rock and wall gardens, borders and patterned beds, pots and dish gardens, no other succulents—except perhaps the sedums—can equal them for easy culture and rugged beauty.

Ofihe smaller species no collection can afford to miss the exquisite Cobweb I louse lee k t S arachnoideum. whose half-inch rosettes are densely covered with cobweb-like white hairs; or the slightly larger, darker green species, 5. montanunu noted for its bright purple flowers. Of the larger sempcrvivums none

Was this article helpful?

0 0

Post a comment