FIRST IMPRESSIONS: Carex pensylvanica is a lovely but fairly common sedge of mesic or dry woods. Plants form large colonies from long strong rhizomes. Foliage is deep green, semi-evergreen and about 1’ long with narrow glossy blades. In early spring whitish spikelets are held above the leaves. In the wild, this sedge occurs in partial sun or shade in well drained or dry acidic woodlands. In landscape situations, Carex pensylvanica is an excellent groundcover or lawn substitute for the shade garden.
HABITAT & HARDINESS: Carex pensylvanica is native to eastern and central North America from Manitoba to Quebec. In the United States plants occur from Maine to North Carolina and west from North Dakota to Arkansas. There are a few isolated occurrences in the lower southeastern states as well.
Plants are indigenous to upland woods, open wooded bluffs and slopes, clearings in woods, oak savannas and upland prairies. Commonly called oak sedge because plants often occur in dry woods where oaks are prevalent.
Hardy from USDA Zones 3-8.
PLANT DESCRIPTION: Carex pensylvanica forms loose leafy tufts. Plants quickly spread into large colonies forming dense mats from long underground rhizomes and stolons.
Foliage is fine textured and bright green. Blades are up to 12” long and about 1/8” wide. The narrow glossy leaves are semi-evergreen through most of the range.
In mid-spring fertile culms rise above the foliage bearing a terminal staminate spikelet with 2-3 smaller pistillate spikelets below. The upright stalkless spikelets are white and feathery with dark purple scales. As seed begins to form, the perigynia on the pistillate spikes become larger to accommodate the achenes inside.
This sedge is about 16” tall with a 2’ spread.
CULTURAL & MAINTENANCE NEEDS: Carex pensylvanica is a sedge for acidic woodlands. Plants prosper in dappled sunlight or part shade. Moist soil is preferred but plants will tolerate average soils and some drought.
This sedge is pest resistant and unpalatable to deer and other herbivores.
In gardens, groundcover plantings should be cut to the ground during late winter.
LANDSCAPE USES: Carex pensylvanica is a valuable Lawn Substitute, Groundcover or Edging Plant for a Shade Garden. This sedge is lovely when planted in a soothing Grouping or Mass. Plants provide Erosion Control and Winter Interest and are appropriate for Deer Resistant Plantings, Low Maintenance Plantings, Water-wise Landscapes and Wildlife Gardens.
Carex pensylvanica is a great native substitute for the popular Asian groundcovers Liriope muscari and Ophiopogon japonicus.
COMPANION & UNDERSTUDY PLANTS: Try pairing Carex pensylvanica with Antennaria neglecta, Chrysogonum virginianum, Heuchera americana 'Dales Strain', Iris cristata 'Tennessee White', Phlox divaricata, Tiarella cordifolia or Polystichum acrostichoides.
Carex albicans is similar in appearance and cultural needs but it lacks long stolons and rhizomes and is slower to cover the ground.
TRIVIA: Plant 1’ apart to create a woodland lawn that can be mown to 3” or slightly lower. Mowing can be scheduled 1 to 3 times a year but a late winter clipping is the most important. Keep moist until established and water deeply as needed or every 2 weeks thereafter. Clumps can be divided in early spring to increase lawn space or groundcover mass.
For more information on this plant, visit the USDA PLANTS Database: http://plants.usda.gov/java/profile?symbol=CAPE6