ISI 2015-29. Haworthia semiviva (Poelln.) M.B.Bayer

As haworthias go, this one has experienced relatively few nomenclatural shufflings. It is so distinctive that only a couple of authors have suggested treating it as a variety of some other species: H. bolusii var. semiviva Poelln., and H. arachnoidea var. semiviva (Poelln.) Halda. While affinity with those widespread and variable species is obvious, the uniqueness of H. semiviva justifies its retention at specific level without much argument from those who spend their time rationalizing their taxonomic tap-dancing. H. semiviva is a strictly winter-growing species, like some of it relatives, but its broad, translucent leaves with prominent lineate veins, stand out. As dormancy sets in, the apical quarter or more of each leaf dries and folds in to protect the growing point during the long dry summer. This habit is the source of the specific epithet, which means “half alive”. As Frank Horwood used to joke, this also means that the plants are “half dead”, on their way to finally succumbing to overwatering. A mostly dry summer dormant period must be observed if one expects to maintain this plant in one’s collection for long. We offer plants from tissue culture of a clone that has survived in cultivation for many years. HBG 101181 was obtained from Seymour Linden in 2003. Seymour received his plant from the late British haworthia specialist Joyce Coccoza, who was known for her superior selections. The species is strictly solitary, recommending it as a candidate for tissue culture. Its range is surprisingly broad, spanning the dry interior of the northern W. Cape and southern N. Cape provinces of South Africa. While the more easterly parts of this range may receive some summer rain, it is best given summer water sparingly, if at all, in cultivation. $10.

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Photo © 2015 by Karen Zimmerman. Images may not be used elsewhere without permission.

Published in the Cactus and Succulent Journal, Vol. 87 (3), May - June, 2015