En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
rate this answer
1 rating

Friday - April 30, 2010

From: Hendersonville, NC
Region: Southeast
Topic: Erosion Control, Grasses or Grass-like, Herbs/Forbs
Title: Need to stabilize a south facing slope in Henderson, NC
Answered by: Jimmy Mills


Hi, I have a south facing slope that is heavy clay with rock under it. It gets a lot of sun. I have planted a few bushes and some ground cover, but with all the snow and rain we had this past winter, part of the slope came down into the driveway felling the 4 foot high retaining wall. I paid a guy $400 to fix the retaining wall. He put black nursery cloth on the top and placed large flat rocks on top of that. What should I plant to keep the soil from sliding again. Its about a 60 degree slope. Thanks


Mr. Smarty Plants can't help you with the retaining wall part, but he can suggest some plants that you can use to help stabilize the slope. We usually recommend grasses for this because their fibrous root system helps to hold the soil particle and prevent erosion. When you hear "grasses" you may think about the turf grasses that require mowing to appear attractive. The grasses we are suggesting are sometimes called ornamental grasses or bunch grasses that require no mowing. Planting a combination of grasses , sedges, and small flowering plants may provide the stabilization that your slope needs. You may want to consult a structural engineer or a landscape architect to deal with the issues concerning the retaining wall.

Lets start by going to our Native Plant Database and scrolling down to the Combination Search box and make these selections; select North Carolina under State, Grass/grass-like under Habit, Perennial under Duration, Sun under Light Requirement, and Moist under Soli Moisture. Click the "Submit Combination Search" button and you will get a list of 45 native plants in North Carolina that match these characteristics.  Clicking on the name of each plant will bring up its NPIN page that contains a description of the plant, its habitat and growing conditions along with images.

For the flowering plants we'll try another approach. Let's go to the RECOMMENDED SPECIES page and select North Carolina on the map. This will give you a list of 135 commercially available native plant species suitable for planned landscapes in North Carolina. Go to the Narrow Your Search box on the right side of the page and follow the procedure as before; selecting Herb under Habit instead of Grass/grass-like. Clicking the Narrow your Search button will trim your list to 18. You can alter either list by going back and changing your choices in the categories.

Here is a short list of grasses and sedges, as well as flowering herbs that you might consider for your hillside.

Our Suppliers Directory can help you locate nurseries close to you that sell the plants that you select.

Grasses and sedges

Andropogon gerardii (big bluestem)

Elymus canadensis (Canada wildrye)    

Schizachyrium scoparium (little bluestem) 

Panicum virgatum (switchgrass)   

Carex pensylvanica (Pennsylvania sedge)  

Carex blanda (eastern woodland sedge)     

Flowering herbs

Physostegia virginiana (obedient plant)  

Monarda fistulosa (wild bergamot)  

Liatris spicata (dense blazing star)  

Asclepias incarnata (swamp milkweed)  

Gaultheria procumbens (eastern teaberry)   

Andropogon gerardii

Elymus elymoides ssp. brevifolius

Schizachyrium scoparium

Panicum virgatum

Carex pensylvanica

Carex blanda

Physostegia virginiana

Monarda fistulosa

Liatris spicata

Asclepias incarnata

Gaultheria procumbens





More Erosion Control Questions

Hillside Erosion in Pace FL
July 17, 2015 - I have a hillside that slopes down about 10 feet to a spring fed pond. The pond drains into Escambia Bay. We have 2 dams with culverts to control the flow of water. Last year during a torrential ra...
view the full question and answer

Removing Texas cedar Juniperus ashei from Blanco River banks
February 26, 2014 - Dear Mr. Smarty Plants, Should cedar trees be removed from our Blanco River banks to prevent them from sucking too much of our precious water before it makes it into the river system? If so, what s...
view the full question and answer

Construction problems on site in Mansfield OH
April 28, 2012 - Last year we had a rectangular above ground pool put in the person who "leveled" for use did a terrible job and basically dug a huge hole for us to put our pool in. The back side of the pool is abou...
view the full question and answer

Shade tolerant plants for erosion from Austin
May 03, 2014 - I live in Austin and my house backs up to Shoal Creek. I am looking for a native creeping vine or something that will grow on the shaded bank to help prevent erosion. It should be able to tolerate the...
view the full question and answer

Shrubs and small trees for a slope in NY
May 21, 2012 - We are looking for a living wall made of shrubs / small trees - no more than 25' for the top of a steep creek bed. We are looking for the best erosion preventing types.
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center