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?

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
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
Not Yet Rated

Saturday - May 04, 2013

From: San Antonio, TX
Region: Southwest
Topic: Groundcovers, Shade Tolerant
Title: Groundcover for shade under oaks in San Antonio
Answered by: Nan Hampton

QUESTION:

I have been modifying my landscape to reduce grass and the need for frequent watering. Have turned half the backyard into native plants garden with hardscape and sitting areas. Have 2 mature Monterey oaks in middle of backyard providing lots of shade, with a large saga palm between them. Can you recommend a ground cover or low-growing plant which will grow in all that shade?

ANSWER:

The biggest problem growing something in the shade of your oaks is, well, all that shade.   Most plants prefer to grow in sun or partial shade.  There are some, however, that will grow quite happily in the shade or partial shade.  Also, there may be a problem growing plants under your oak tree, not just because it will be shady but because the oak tree has an allelopathic effect on some other plants.  Allelopathy is a situation where a plant releases a chemical that has an effect on another plant.  The effect may be beneficial or harmful, but the ones we hear about the most are those that are harmful to another plant.  One of best known of the allelopathic plants is the walnut tree (Juglans spp.).  It has a very strong effect on most plants attempting to grow beneath it.  Trees with a lesser allelopathic effect include oaks, hackberries and eucalyptus trees.  Red oaks, which in your area would be Quercus buckleyi (Texas red oak), are mentioned more often than other oak trees.  You can read more about allelopathy in this article, Allelopathic plants: nature's weedkillers.  That said, not all plants are susceptible to the oak's chemicals.  Some plants can grow under oaks.  I couldn't find a list of plants native to Texas that reportedly grow under oaks, but I have seen the following growing happily under oaks:

Carex blanda (Eastern woodland sedge) is evergreen.

Carex planostachys (Cedar sedge) is evergreen.

Carex texensis (Texas sedge) is evergreen.

Chasmanthium latifolium (Inland sea oats) is perennial and turns golden brown in the winter.  You can cut them back down to the new green rosettes forming in the early spring to show their vibrant new growth.  They are happy growing in the shade of oaks.  This grass grows 2 to 4 feet and is very attractive.

Calyptocarpus vialis (Straggler daisy) will probably remain evergreen in San Antonio and do just fine under oaks.

Geum canadense (White avens) is evergreen and can be mowed.

Packera obovata (Golden groundsel) will form an evergreen ground cover.

Salvia lyrata (Lyreleaf sage) makes an evergreen ground cover.

Paxistima myrsinites (Mountain lover)  Here are photos and more information from Southwest Colorado Wildflowers.

 

From the Image Gallery


Eastern woodland sedge
Carex blanda

Cedar sedge
Carex planostachys

Texas sedge
Carex texensis

Inland sea oats
Chasmanthium latifolium

Straggler daisy
Calyptocarpus vialis

Straggler daisy
Calyptocarpus vialis

White avens
Geum canadense

White avens
Geum canadense

Golden groundsel
Packera obovata

Golden groundsel
Packera obovata

Lyreleaf sage
Salvia lyrata

Oregon boxleaf
Paxistima myrsinites

More Groundcovers Questions

Locating free tumbled glass for mulch in Austin
October 31, 2008 - Do you know where tumbled glass can be obtained for free in Austin? You've used it as a mulch at the Center. Someone in one of my Native U classes mentioned that it can be gotten free somewhere in ...
view the full question and answer

Horseherb planting in Richardson, TX
October 18, 2014 - What is the best time to plant 4" pots of Horseherb?
view the full question and answer

Alternative to grass as groundcover in area used by dog
January 05, 2007 - I am looking for a beautiful groundcover to use instead of grass which need to be soft and animal friendly. My dog is in the yard a lot and she's 10 yrs old. I am looking for a groundcover which wi...
view the full question and answer

Low-growing plants for a slope in the shade
July 08, 2013 - Hello, I'm looking for native plants to put in the shade (within the drip-line) of a well-established American Holly. The area gets deep shade; it is also on a very gentle north-exposure slope. We ...
view the full question and answer

Groundcovers for hillside in Northern California
November 19, 2012 - I have read numerous posts on here, but I have not found my exact situation. I live in Northern California. I am looking for some type of ground cover to grow on a hillside. Directly above the hillsid...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2015 Lady Bird Johnson Wildflower Center