Plant in full sun to light shade. Once established it has shown moderate drought resistance, especially in part shade, or plant in full sun with average to occasional garden water. It is cold hardy and useful in USDA Zone 4 and above. This sedge is a moderately slow but a steady spreader in a low-water use garden, but spreads much more rapidly with ample water and fertilizer. A great groundcover for that cool blue feel; taking some traffic or it can be used directly in a water garden planted up to 2" below the water surface. Spreads slowly with runners which can be encouraged by trimming back lightly – a mowing set at 4 inches high done three to four times a year keeps this plant vigorous and neat.

Carex flacca is from the area around the Mediterranean Sea where it grows in calcareous grasslands, sand dunes and in estuaries in Europe and North Africa. The name for the genus is a Latin word describing the sedges and the specific epithet is from the Latin word 'flaccus' that means "weak", "limp" or "drooping' in reference to the way the pliable foliage lays over.

This plant it long initially offered by nurseries in the US as Carex glauca, the name under which we listed it for over 20 years since we first began growing it in 1986 from plants purchased from "the grassman", John Greenlee. The correct name for this plant however is Carex flacca, though arguably this form sold for many years in the nursery trade is a very nice glaucous form of this species. The name Carex flacca is not a name change but the confusion between these two names for the same plant that has been going on for centuries. The Department of Botany of the British Museum first discusses this in their 1898 report and cites the reason why the name C. flacca takes precedence. Carex flacca was described by German botanist and zoologist Johan Christian Daniel von Schreber (1739-1810) in 1771 and a year later (1772) Giovanni Scopoli (1723-1788), an Italian physician and naturalist, described a plant he called Carex glauca. Once it was determined that these plants were the same species, the older name should have taken precedence, but apparently the older name, Carex flacca, was at first overlooked and Carex glauca came into more common usage. This has been corrected by many but both names still seem applied to this same plant.

We have grown and listed this continuously in our nursery catalogs since 1987. We also grow a taller and narrower leaf selection of Carex flacca called 'Blue Zinger'. In recent years there has surfaced concerning news of Carex flacca naturalizing in wildlands of Connecticut, Vermont, Kentucky, Michigan, and New York, and also in the Canadian provinces of Nova Scotia, Ontario, and Quebec. This has not been observed in our drier mediterranean climate where this plant has not reseeded outside of irrigated areas and only rarely reseeded even in irrigated locations, but it is certainly something to be aware of. 

The information displayed on this page about Carex flacca is based on our research conducted about this plant from books in our nursery library as well as from information that is provided by reliable online resources. We also have included our own observations made about it as it grew in the nursery gardens and other gardens visited, as well how the crops of this plant performed in the containers when we had them in our nursery field. We also include comments received from others and welcome hearing from anyone who has information about this plant, particularly if it includes cultural information aiding others to better grow it.