Host an Event Volunteer Join Tickets

Support the plant database you love!

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?

Share

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
2 ratings

Wednesday - March 04, 2015

From: Austin, TX
Region: Southwest
Topic: Meadow Gardens, Planting, Groundcovers, Herbs/Forbs
Title: Compatibility of mixed ground covers with St. Agustine grass
Answered by: Guy Thompson

QUESTION:

My husband and I live in Northwest Austin. We have removed lawn from our front yard and replaced it with mulch and some trees and other plantings. We would like to replace the lawn in our backyard with several groundcovers. We especially like frogfruit, henbit, and horseherb. If we plant them in abundance, can these plants outcompete our lawn, which consists of St Augustine, with some Bermuda grass? Or do we have to remove the lawn? Also, do groundcovers "play well" together? I'd love to have a mix of several varieties, but I don't want to create a groundcover war! Thank you.

ANSWER:

I recently had an experience much like yours.  I replaced the St. Augustilne grass in part of my lawn with Habiturf, the mixture developed at the Wildflower Center for water conservation.  Habiturf does not thrive in shade, which I have in one part of the lawn.  So I planted in that part a number of mowable forbs and sedges that grow in my neighborhood, and, unlike you, looked forward to a groundcover war to discover the fittest species.  I wanted a lawn of mixed grass and various forbs.

Here are some of the species I tried, and I indicate after each whether they grew well (G) among the sparse grass or struggled (S).  Carex blanda (Eastern woodland sedge)(G), Carex texensis (Texas sedge)(G), Carex planostachys (Cedar sedge)(G, but did not spread), Calyptocarpus vialis (Straggler daisy) (GG, but in late Spring), Ruellia humilis (Fringeleaf wild petunia)(G), Phyla nodiflora (Texas frogfruit)(G, but straggly), Salvia lyrata (Lyreleaf sage)(G), Dichondra recurvata (Oakwoods ponysfoot) (GGG), Viola pedata (Birdfoot violet) (S), Salvia roemeriana (Cedar sage)(G, but did  not spread), Oxalis stricta (Common yellow oxalis) (GGG) and Oenothera speciosa (Pink evening primrose)(S). I expect that those species that are successful will coexist fairly peacefully.

Seeds from Lupinus texensis (Texas bluebonnet) and Gaillardia pulchella (Firewheel) somehow found their way in and germinated freely in the sunny spots the second season.  Echinacea purpurea (Eastern purple coneflower) (S) encroached from a nearby bed.  I am keeping some non-natives, e.g., ajuga, which quickly invaded the shady lawn without my permission but I am pulling out chickweed and henbit, which also do well.  I mow every several weeks in Summer, skirting around taller bloom stalks.

Now for the question of whether some or all of these would do well in St. Augustine.  I notice Wild petunia, Straggler daisy and Lyreleaf sage occasionally growing in my other (St. Augustine) lawn without any encouragement from me. But I think most of the species I mentioned would have trouble competing with St. Augustine, especially in full sun.  You would have to give them some help.  I have read that these plants grow better in Habiturf if it is cut short, given lots of water, and/or fertilized heavily.  That might help with St. Augustine too.  Otherwise, you will have to prune away the grass from around the forbs until they get a good start.  This would be much more effective in shady or even partly shady spots.

I have enjoyed both the successes and the failures, and I think you will too.

 

 

From the Image Gallery


Eastern woodland sedge
Carex blanda

Cedar sedge
Carex planostachys

Horseherb
Calyptocarpus vialis

Prairie petunia
Ruellia humilis

Texas frogfruit
Phyla nodiflora

Lyreleaf sage
Salvia lyrata

Oakwoods ponysfoot
Dichondra recurvata

Birdfoot violet
Viola pedata

Cedar sage
Salvia roemeriana

Eastern purple coneflower
Echinacea purpurea

Common yellow oxalis
Oxalis stricta

Pink evening primrose
Oenothera speciosa

More Groundcovers Questions

Native plants for memorial garden in Michigan
March 04, 2008 - I want to start a memorial garden for my daughter. I live in northern Michigan and the area has very tall white pines we have pruned them up about 15' so the area does get partial sun. Which plants w...
view the full question and answer

Filler for between flagstones in Michigan
July 05, 2014 - I have a natural shoreline project underway (replacing a seawall) with all native Michigan plants replacing the lawn as well. A flagstone walkway is going in and I wanted "moss" type filler in betw...
view the full question and answer

Narrow strip of groundcover from Sonora TX
April 29, 2013 - I have an area that is right under my patio about 12 feet by 1 ft. I'm looking for something to plant in there. It has afternoon sun, morning shade. I live in SW Texas so it is hot. but would like so...
view the full question and answer

Plants for a mixed border in Houston
February 22, 2010 - I live in Houston and have a flowerbed I'd like to fill with plants that will look good year-round. The back is already lined with 6-foot shrubs so nothing like that. I'd like something with colorf...
view the full question and answer

Plantings for a slope from New Carrollton MD
June 27, 2012 - My house (Maryland, near DC) sits at the bottom of a south facing slope. The soil is very heavy clay. The grade is about 1:20 for about 100 feet (with a steeper part at the top). Part of the hill is i...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.