Carex is a large genus of grass-like perennials that are found in nearly all corners of the planet. Eastern North America alone hosts hundreds of species, although relatively few of these are available commercially. The genus Carex belongs to the Cyperaceae plant family. Members of this family are commonly referred to as sedges. Sedges may resemble plants in other families such as the Poaceae (grasses), but Carex have specific anatomical features such as triangular stems and unisexual flowers that set them apart.
Carex pensylvanica ‘Straw Hat’ (Straw Hat Pennsylvania sedge)
The diversity of Carex matches the wide spectrum of habitats in which they grow, from shaded wetlands to coastal sand dunes and almost everything in between. In the garden, some Carex species are surprisingly adaptable to conditions outside of their typical wild preferences. Carexmay be planted en masse to cover ground, stabilize soil, and suppress weeds, and some species are so striking that they can be used as individual specimens and accents. In a typical cultivated landscape, Carex are low maintenance, requiring a late winter or early spring cutback, but many species thrive even without this level of care.
Carex cherokeensis (Cherokee sedge)
Mt. Cuba Center’s four-year Carex trial evaluated the horticultural qualities, vigor, and adaptability of 70 different Carex species and cultivars. Plants were grown in shade and sun in average garden soil. In the final year of the trial, response to biweekly mowing was recorded to assess potential as a lawn substitute.
Multiple plants of each taxa are grown in their a 15,000 sq. ft. trial garden that includes areas for growing both sun-loving and shade-loving plants. The clay-loam soil in the trial garden has an average pH of 6.5.
The Trial Garden is maintained with the home gardener in mind. Plants are watered as needed during the first year in order to get them established, but afterwards they are left on their own. Pesticides are not used unless there is a serious threat to the entire trial’s survivability.
Perennial plant trials usually run for a period of three years to ensure the plants experience a variety of weather conditions. It is our policy to replace dead plants after the first winter in order to compensate for poor establishment or initial plant quality. However, no replacements are made during subsequent years. Each taxa is evaluated weekly and assigned a rating based on a scale of 1-5 (see below). This rating takes into account many factors including habit, floral display, disease resistance, hardiness, and foliage quality. The average of these weekly ratings is then used to calculate the final score displayed on this website.
Click here to view the research report or scroll down for detailed descriptions about each plant in the trial (top performers plus all other plants tested) in alphabetical order.