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Wednesday - January 23, 2013

From: Falls Church, VA
Region: Mid-Atlantic
Topic: Erosion Control, Grasses or Grass-like, Herbs/Forbs
Title: Need suggestions for plants for a 45 degree slope in Falls Church, VA.
Answered by: Jimmy Mills


Have a 45 degree hillside 50 feet wide by 60 feet long on north side of 26 story building. Very little sun with the need for soil retention plants. Would like a native plant or plants to cover area. Additionly perenials for color. Any suggestions. Thank you.


When it comes to stabilizing slopes, we most often recommend planting grasses/grass-like plants because their fibrous root systems hold on to the soil particles.  Grasses generally evolved in the plains and are mostly sun-loving plants. However, there are a few that will grow in partial shade.

To look for plants, lets go to our Native Plant Database which contains 7,372 plants that are searchable by scientific name or common name. Scroll down to the Combination Search Box and Select Virginia under State, Grass/grass-like under General Appearance, and Perennial under Duration. Check Part shade under Light requirement, Dry  under Soil moisture, and 1-3 ft. under Size Characteristics. Click on the Submit combination Search button, and you will get a list 9 native species of plants that meet these criteria. Clicking on the Scientific Name of each plant will bring up its NPIN page which has a description of the plant along with growth characteristics and requirements, and images in most cases.

To look for flowering perennials, go to the Narrow Your Search box located on the right of the page and change Grass/grass-like to Herb under General Appearance, leaving all of the other selections the same. Click on the Narrow Your Search button and you will get a list of 52 flowering plant species.

Another useful source of information are the USDA Distribution Maps for each of the plants. To access these; scroll down the NPIN page for the plant to the box labeled ADDITIONAL RESOURCES. Clicking on the name of the plant beside USDA will bring up the Plants Profile page for the plant. Scroll down to the map of the US which has the states where the plant naturally occurs in green. Clicking on Virginia will bring up a map that shows the counties in Virginia where the plant occurs.

We frequently get questions about growing plants on steep slopes, and I’m going to share the answers to three of these with you.




You may also want to contact the folks at theFairfax County Office of Virginia Cooperative Extension for some help closer to home.


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