Explore Plants

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
    
 

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:

 

 

 

More Trees Questions

Magnolia Not Doing Well in Round Rock, Texas
June 25, 2011 - I have a Magnolia grandiflora in my back yard, planted on May 20th of this year. Located on a western exposure with no shade and about 18' tall x 10' wide. I've been watering it every 3-4 days or ...
view the full question and answer

Distance from existing structures for live oak
April 18, 2009 - How close to your house slab, driveway and footpaths should you plant live oaks so as to avoid in the future damage from roots, falling branches, etc?
view the full question and answer

Proper watering of cedar elm trees in Sachse, TX
August 15, 2008 - I've just planted two Cedar elm trees in clay soil, each about four inches in diameter, and I want to water them correctly. I'm aware that too much water can be bad as well as too little water. I ...
view the full question and answer

Leaves on 3 year old maple turning brown in Lebo, KS.
July 16, 2011 - Hello, one of our five Maple trees which is is 3 yrs. old now, we saw a week ago that the leaves started turning brown and dropping. My question is: Will the tree survive this and return healthy next ...
view the full question and answer

Need options for smaller trees in neighborhoods in Austin, TX.
May 25, 2012 - Please discuss smaller tree options for typical Austin neighborhood yards. These houses are built close together on the sides, and only have smallish back yards. They just don't have space for big 50...
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.