En Español

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

Thursday - April 09, 2009

From: Philadelphia, PA
Region: Mid-Atlantic
Topic: Erosion Control, Grasses or Grass-like
Title: Water seepage problems in basement in Philadelphia
Answered by: Barbara Medford


I am interested in stopping/limiting water seepage into my basement by placing water absorbing ground plants along one or both sides. The grass we planted when home was new in July 2007 has taken on one side but not on smaller fenced/shaded walkway. Property is in Philadelphia, PA. I am looking for recommendations.


Your problem with water seepage is a little out of our line. We are going to refer you to some websites that will help you determine a possible cause for the problem. First,  Do It Yourself Tips on Basement Waterproofing is from an association of paint manufacturers, so their solution is obvious but one you may want to consider. This one from eHow website How to Troubleshoot a Wet Basement mentions repairing the grade of your soil so that it drains away from your foundation and checking to make sure gutters and downspouts are properly placed to drain water away. You really should have someone who is an expert on this kind of problem look at it and make sure there is not a more serious underlying problem and recommend an appropriate fix.

However, we can suggest plants with fibrous roots that will absorb water and hold the soil after you have corrected the drainage problem. To us, this means native grasses, which have long fibrous roots and are great at holding soil. It would be best to make whatever soil gradient or drainage corrections you have to make first, as the grasses alone will not solve the problem, and you would have to disturb or dig up those grasses later if you did not do the basic work first.

The grass you planted was probably a non-native turf grass that needs sun to flourish, but is not necessarily as good at holding soil. We can recommend grasses native to Pennsylvania both for the sunny and shady sides of your house which will be attractive and certainly help to keep the soil from shifting after you have made the necessary changes. In terms of which grasses to use where, we consider full sun to be 6 hours of sun or more a day, part shade 2 to 6 hours of sun, and shade less than 2 hours of sun a day. Before you make a selection, keep records for a few days of how long there is sun at each spot. Some of the grasses will tolerate full sun, part shade and shade, so we will mention what the light requirement for each is to help you find the right grass for the right spot. 

Native Pennsylvania Grasses for Water Absorption

Andropogon gerardii (big bluestem) - 4 to 8 ft. tall, sun, part shade

Bouteloua curtipendula (sideoats grama) - 2 to 3 ft., sun

Bromus kalmii (arctic brome) -  2 to 3 ft., sun

Carex blanda (eastern woodland sedge) - 1 to 3 ft., sun, part shade, shade

Calamagrostis canadensis (bluejoint) - 3 to 5 ft. sun, part shade, shade

Chasmanthium latifolium (Inland sea oats) - 2 to 4 ft., part shade, shade

Elymus canadensis (Canada wildrye) - 2 to 4 ft., sun, part shade

Schizachyrium scoparium (little bluestem) - 18 to 14 inches, sun, part shade

Andropogon gerardii

Bouteloua curtipendula

Bromus kalmii

Carex blanda

Calamagrostis canadensis

Chasmanthium latifolium

Elymus canadensis

Schizachyrium scoparium



More Erosion Control Questions

Plants for erosion control in Georgia
May 17, 2010 - Hello, I have a question regarding water run-off coming from the neighbors yard as my yard is below their yard. What kind of ground cover would grow very quickly (low to ground) to help with the r...
view the full question and answer

Use of native grasses as erosion control in Austin, TX
June 20, 2006 - We're in Austin, TX and trying to keep our neighborhood lot as natural as possible; however, our lot is eroding and depositing mud and dirt onto the sidewalk whenever it rains. We're looking for an ...
view the full question and answer

Need plants to replace cedars on a 40 degree slope in Boerne, TX.
August 28, 2012 - My backyard is a roughly 40 degree slope that is covered with cedars. The slope is basically all rock, what can I grow here to replace the cedar which drink too much water. I would still like the area...
view the full question and answer

Plants for steep slope in shade in Iowa
July 02, 2010 - I work for a small non-profit shelter here in Dubuque, Ia. that has a very steep slope behind the building that needs some sort of plant or grass planted to stop erosion. The slope gets little to no s...
view the full question and answer

Plants to prevent creekside erosion in Nacogdoches County, Texas
December 09, 2014 - I am looking for some advice on plants native to Texas that can help prevent erosion. I own a wooded lot with a creek and would like to consolidate the sides of the creek against potential erosion. I...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center