From coast to coast, look along the edge of any pond or marsh, and you're bound to find a patch of sedges (Carex spp.). There are more than a thousand species worldwide, though relatively few are used in gardens. Sedges are grasslike plants (not true grasses) with foliage in an astonishing range of colours and textures but with insignificant flowers. In recent years, an influx of new species and cultivars have been snatched up by gardeners who appreciate their unique foliage characteristics. Here are some worthwhile examples.
Aptly named, all the plants in this group have extremely narrow leaves with a hairlike texture and are clump-forming. Primarily native to New Zealand, they only survive reliably in Canada where winters are mild (Zones 7 to 8). But in colder regions, hair sedges can be grown by gardeners for a single season in containers or in the garden as half-hardy perennials or annuals. With leaves in shades of cinnamon, bronze, orange, blond or green, hair sedges have a quirky, wig-like look that is unusual yet appealing. Bronze hair, leatherleaf and ‘Frosted Curls' sedges sometimes self-sow, especially in gravel pathways. These types are easy to start from seed indoors or to propagate by division.
The hardiness of this group has proved problematic in areas with tough winters. Although many are evergreen species and survive in Zones 6 and colder, by winter's end they can look pretty beat up. The dead leaf tips can be snipped off with scissors, but it's a tedious job. Several plants in this group share the common name “variegated Japanese sedge,” with the most widely grown being ‘Evergold', which resembles a narrow-leafed spider plant; Gold Fountains sedge is more vigorous. Broad-leafed sedge, the hardiest Japanese type, resembles a narrow-leafed hosta. Even more striking recent selections include ‘Banana Boat', ‘Lemon Zest' and Island Brocade, but, sadly, all of these perform best only in Zones 7 to 8.
Other Useful Sedges
One of my very favourites is the tropical-looking palm branch (or palm) sedge, a native North Ameri-can species. If unleashed to grow in rich, moist soil, it forms a large patch, but it also does well in sizable containers submerged in ponds. (In my Zone 6 garden, I leave the pot and all in the water throughout the winter, and the plant comes up each year without a problem.) The morning star sedge is another moisture lover. It's the only garden species with interesting seed heads, which are light green and shaped like medieval maces. Totally overlooked and undervalued is blue creeping sedge (or carnation grass)-a true workhorse, especially as a low-spreading groundcover. Its narrow, blue-green leaves, although evergreen, benefit from a quick trim or mowing in early spring to tidy up any damage from winter windburn.