Green Roofs - Living Architecture Monitor - Fall 2012 - (Page 16)

PLANT PROFILE tough PLants: sedum kamschaticum and its kin IN EACH ISSUE WE pROfILE A GREEN ROOf OR WALL pLANT, ExpLORING ITS BIOLOGy, USES AND pREfERENCES. By: MARGUERITE WELLS T he Allium genus is part of the Lily family, Lilaceae. This species and its variants are very popular green roof plants—with good reason. Let’s explore some of the variety available. Taxonomists take a wicked pleasure in reclassifying and renaming plants on a regular basis, as our understanding of their genetic relationships change. This has led to many names for the same plants. I will try to clarify a bit below. Sedum kamschaticum: The plain species, to which all the others are related, is a workhorse on roofs. They have medium green leaves, yellow flowers, are clump forming in habit, extremely drought-tolerant and can take some shade. Cuttings root much better in spring than fall, when the plant is preparing to drop its leaves for winter. Sedum kamschaticum variegatum: The variegated form of the plain species, with white margins on the leaves. Attractive close up, but on a green roof this difference is mostly not apparent. All variegated plants are weaker forms of the plain species, since some portion of their photosynthetic area is white, not green, therefore not contributing to the plant’s upkeep and growth. Sedum kamschaticum. cv. floriferum ‘Weihenstephaner Gold’: The two varieties of floriferum were once consid- ered their own species, but have now been brought under the kamschaticum umbrella by taxonomists. To save on the mouthful of a name, it also is called ‘Bailey’s Gold’. Much smaller leaves, more mat forming, and more evergreen than the plain species. An extremely tough plant. Sedum k cv. floriferum ‘sichotense’: At some times of year, and some conditions, this plant is indistinguishable from Weihenstephaner Gold, but overall a taller plant, with longer, pointier leaves. It flowers exactly two weeks after Weihenstephaner Gold, and its leaves turn scarlet in fall, unlike its kin. There is another plant called Sedum sichotense, which looks similar, but rare in cultivation. Sedum kamschaticum var. ellecombianum, aka Sedum ellecombianum and selskia-

Table of Contents for the Digital Edition of Green Roofs - Living Architecture Monitor - Fall 2012

Green Roofs - Living Architecture Monitor - Fall 2012
From the Founder
Letter From the Editor
The World’s First Bio-Façade Ready to Grow
Save the Dates for the Greenroofs & Walls of the World™ Virtual Summit 2013
On the Roof With…
Policy and Standards
Current Research
2012 Awards of Excellence
New Corporate Members
Professional Calendar
GRHC Buyer’s Guide
On Spec

Green Roofs - Living Architecture Monitor - Fall 2012