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 - January 30, 2010

From: Clover, SC
Region: Southeast
Topic: Trees
Title: What plants to put under an oak tree in Clover SC
Answered by: Barbara Medford

QUESTION:

I have a 70 year old oak tree in my backyard and have tried to grow grass out from it with no success. I'd like to just plant some shrubs and make it a natural area now, but need advice on what I can plant near the oak, not directly under it. The area where I want to create a garden is about 10-12 feet from the oak. I've planted flowers away from the oak in the past, but nothing has done well. Any suggestions on shrubs or flowers that I would do well about 10 ft away from the oak? Also, would it be better to create a large raised bed and create a garden area that way?

ANSWER:

An oak tree that old is a valuable landscape asset, so your first question should probably be: "What will not harm the tree?" Oak trees do not like competition. Their heavy shade in summer, and the year-round presence of the root system are disadvantages for plants beneath the oak. Furthermore, the mature oak is known to have the quality of allelopathy, which means they emit substances that will inhibit the growth of plants beneath them; these substances can come from roots, twigs, or leaves. You say you plan to plant 10 to 12 feet from the oak, we assume that is from the trunk. A tree that old likely has a pretty impressive canopy, and the roots can extend out up to three times the circumference of that canopy.

Next, your idea of making a raised bed would possibly permit you to grow some plants, but it would not be good for the oak. These far-reaching roots we described reside mostly in the upper 12 inches of the soil. That characteristic is to ensure the roots have easy access to moisture, nutrients and oxygen. Piling soil up on those roots might not damage the tree right away, but in the long run it could begin a die-back of the most affected areas, eventually becoming an unattractive liability. If you dig holes for shrubs in the ground level, without raising the bed, you will both be destroying roots of the tree and putting roots of the shrubs in competition with the roots of the tree, whch is advantageous to neither.

We don't like to sound so negative, but we also would hate for you to waste time and resources putting in plants that will not thrive and possibly damaging your tree, as well, in the process. One possibility might be to put down a good quality shredded bark mulch beneath the tree, and perhaps ring that mulch with shrub beds having the same mulch in them. They would blend together nicely and look natural. With that in mind, we are going to recommend some shrubs native to South Carolina that will tolerate sun or part shade. We tried to choose some that are considered "understory" plants; i.e., they should do pretty well at coping with interference from trees. Follow each link to the page on that plant to learn other characteristics and growing conditions. 

Shade or Part Sun Shrubs for Cover SC:

Callicarpa americana (American beautyberry) - 3 to 5 ft. tall, deciduous, blooms white, pink May to July, part shade

Comptonia peregrina (sweet fern) - 2 to 4 ft., blooms white, green May to August, part shade

Hydrangea arborescens (wild hydrangea) - 3 to 6 ft., deciduous, blooms white, green June to August, part shade

Hypericum prolificum (shrubby St. Johnswort) - to 3 ft., deciduous, blooms yellow June to August, part shade or shade

Symphoricarpos orbiculatus (coralberry) - 4 ft., deciduous, blooms white, green April to July, part shade or shade

From our Native Plant Image Gallery:


Callicarpa americana

Comptonia peregrina

Hydrangea arborescens

Hypericum prolificum

Symphoricarpos orbiculatus

 

 

 

More Trees Questions

Why is Rhus aromatica more deer resistant from Seattle
December 07, 2009 - I have a large area that I would like to cover with Rhus aromatica. My landscaper says that in his experience, Rhus typhina and glabra in this area are heavily browsed by deer. I noticed in your dat...
view the full question and answer

Split trunk in Bald Cypress in Uhland, TX
May 31, 2009 - I live just south of Austin, and near the pond (stock tank) is a bald cypress, young, about 12-15 yrs., and after this past year, drought and all, I was dismayed to find it not leafing out. When I in...
view the full question and answer

Control of live oak root sprouts, or suckers, under tree
September 19, 2007 - Have live oak trees in clusters with circular beds surrounding in frontyard. Have been invaded by some type weed that looks a bit like holly. Woody stem a few inches high with several serrated leave...
view the full question and answer

Vehicle friendly oak trees for Austin
March 30, 2008 - Do Chinquapins, Shumards or Live Oaks produce lots of tree sap? I'm looking for a vehicle friendly Oak tree to be installed in parking areas in Austin, Texas.
view the full question and answer

Yellowing leaves on weeping willow
August 03, 2008 - We have a 4 year old Weeping Willow, 12+/- ft. tall and this week the leaves are starting to become yellow. This willow is full and robust in appearance, best it's ever looked. We have 2 other Wee...
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