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Thursday - April 25, 2013

From: Pittsburgh , PA
Region: Mid-Atlantic
Topic: Soils, Erosion Control, Grasses or Grass-like, Herbs/Forbs, Shrubs
Title: Plants for steep slope in Pittsburgh PA
Answered by: Barbara Medford


I have a similar question to one from SC. I live in Pittsburgh, PA. We have a steep slope behind a newly built in pool. What type of plants can I put on the hillside to hold the soil. It gets a lot of sun. There is also a lot of rock under the soil. I appreciate your answer.


We believe this is the previous Mr. Smarty Plants question to which you are referring; we just answered that one a few hours ago so there may be others that you saw, but we understand you are interested in erosion control on a steep hill. The one we linked you to from South Carolina had the problem of a clay soil, which is very difficult to work with, especially for plants that need good drainage for their roots. Since we don't know what your soils are in Allegheny County in the southwestern part of Pennsylvania we will try again to find native plants that are native to your area, counting on the fact that they are native to indicate they will grow in whatever soil, climate and rainfall you have.

We will go to our Native Plant Database, scrolling down to our Combination Search. Then we will select on Pennsylvania for State, run 3 different searches, one on grasses and grasslike plants, one on shrubs and one on herbs (herbaceous blooming plants). For each search we will indicate "sun" under light requirement.  The grasses, of course, are our preference because their long fibrous roots will help to hold the soil, but there are also shrubs and flowering plants that will help the looks of the hillside. These grasses will all be taller native grasses, not lawn grasses, as you would obviously prefer not to mow a hillside. You can follow each plant link to our webpage on that plant to learn growing conditions, moisture needed and best propagation practices. You may, of course, rerun these searches making different specifications and your own choices.

Grasses for Allegheny County, PA:

Andropogon gerardii (Big bluestem)

Carex texensis (Texas sedge)

Schizachyrium scoparium (Little bluestem)

Sorghastrum nutans (Indiangrass)

Shrubs for Allegheny Co., PA:

Amelanchier stolonifera (Running serviceberry)

Hibiscus moscheutos (Crimsoneyed rosemallow)

Rosa blanda (Smooth rose)

Symphoricarpos albus (Common snowberry)

Herbaceous Blooming Plants for Allegheny Co., PA:

Agalinis purpurea (Purple false foxglove)

Antennaria plantaginifolia (Plantain-leaf pussytoes)

Aruncus dioicus (Bride's feathers)

Asclepias tuberosa (Butterflyweed)


From the Image Gallery

Big bluestem
Andropogon gerardii

Texas sedge
Carex texensis

Little bluestem
Schizachyrium scoparium

Sorghastrum nutans

Running serviceberry
Amelanchier stolonifera

Crimsoneyed rosemallow
Hibiscus moscheutos

Smooth rose
Rosa blanda

Common snowberry
Symphoricarpos albus

Purple false foxglove
Agalinis purpurea

Plantain-leaf pussytoes
Antennaria plantaginifolia

Bride's feathers
Aruncus dioicus

Asclepias tuberosa

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