Native Plants

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Monday - April 20, 2015

From: Brevard, NC
Region: Southeast
Topic: Grasses or Grass-like
Title: Groundcover for Slope in NC under Black Walnut
Answered by: Anne Van Nest

QUESTION:

Please advise on some plants for a difficult to mow 30% slope, near Asheville, NC. We have partial sun, plenty of good rich topsoil, and plenty of rain. The key issue is that it is under and near the drip edge of huge black walnut trees. Our hill currently has successful, established turf grass but it is too difficult to mow. We would appreciate your recommendations for year-round groundcover that will intermingle with the existing grasses, survive the juglone of the black walnut trees, and not require mowing.

ANSWER:

The Kansas State Research Extension and the Master Gardeners of Johnson County have produced a factsheet on Selecting Joglone-Tolerant Plants that lists Carex (sedges) as being presumed safe to use around black walnuts. Also the online Black Walnut Dispatch have noted that they have seen Carex growing right at the drip line of Black walnuts.

So why not try some grass-like plants for your slope that are short enough that you don’t have to mow them.

The ones that are native to NC are:

Carex cherokeensis (Cherokee sedge)

Carex eburnea (Bristleleaf sedge)

Carex echinata (Star sedge)

Carex texensis (Texas sedge)

Texas Sedge, is a good turf substitute for dry to moist shade, colonizing densely by rhizomes. Its fine-textured foliage mixes nicely with other small, shade-loving plants like Cedar Sage (Salvia roemeriana), Baby Blue Eyes (Nemophila phacelioides), and White Avens (Geum canadense) to create a serene woodland garden. It can be mowed at a high setting.

From the Image Gallery

Cherokee sedge
Carex cherokeensis

Texas sedge
Carex texensis

Black walnut
Juglans nigra