Native Plants
![](../_images/smarty_plants.gif)
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
![](../_images/mr_smarty_plants_logo_web_200w.jpg)
rate this answer
![](../_images/star_43.gif)
Saturday - August 02, 2014
From: New Haven, MO
Region: Midwest
Topic: Problem Plants, Shade Tolerant, Herbs/Forbs, Trees
Title: Magnolia species are allelopathic
Answered by: Nan Hampton
QUESTION:
Have a healthy Southern Magnolia tree around 8 years old. It seems like everything I plant next to it dies.: Variegated Spirea, Stokes Aster, Hydrangeas. Is there something it secretes like the walnut trees do that kills certain plants? Thanks.ANSWER:
You are absolutely right that magnolias produce chemicals that leech into the soils around it from fallen leaves, twigs and flowers that affect the growth of many other plants. The chemicals are sesquiterpene lactones. Here is a link to a previous question sent to Mr. Smarty Plants explaining allelopathy and magnolias. As well as the allelopathic effects of the magnolia, it is often difficult to find plants that will grown in the dense shade provided by the magnolia canopy. The SF Guide's article, What Flowers Grow under Magnolia Trees, suggests some flowers that will grow there, but they are not all native plants and if native, are not native to Missouri. You can find native plants that are recommended for Missouri on our Recommended page. Using the NARROW YOUR SEARCH option in the sidebar, choose "Herb" from the GENERAL APPEARANCE slot and "Shade" from LIGHT REQUIREMENT to limit the list small plants that grow well in the shade. Here are a few that might be able to resist the allelopathic effects of the magnolia.
Asarum canadense (Canadian wild ginger)
Aquilegia canadensis (Eastern red columbine)
Athyrium filix-femina (Common ladyfern)
Lobelia cardinalis (Cardinal flower)
Sanguinaria canadensis (Bloodroot)
If you do the search above, you can find more plants.
The best way to fight those allelopathic effects are to keep the leaves, twigs, etc., from the magnolia picked up from under the tree.
From the Image Gallery
More Shade Tolerant Questions
Screen plants for part shade in Smithville, TX
February 23, 2010 - Thank you very much for your reply to my question about planting bamboo. I had no idea it was so invasive. I would appreciate any suggestions you might have for me.
My goal is to provide a soft an...
view the full question and answer
Tree as shade alternative to carport in Austin
April 21, 2010 - Hello,
I'm looking for a small tree that could provide afternoon shade for two cars, as an alternative to a carport. When mature, the tree would need to be tall enough to grow around (and above) the...
view the full question and answer
Choice of shade trees from the City of Austin
March 29, 2011 - I have a choice of three shade trees from the city of Austin. They are Live Oak, Elm, Cedar. Although I am happy to have a free tree, I think the choices are not the best for my home. I have a small ...
view the full question and answer
Vines for shade in Central Texas
February 04, 2008 - We'd like to fill in our long expanse of yard fencing with climbing vines. We are limited by 40' live oaks that cut off the sun but surely something works in the shade and heat!
view the full question and answer
Enough sun from San Marcos TX
February 22, 2013 - I would like to plant both Lantana urticoides and Salvia farinacea in area that only has morning to 1pm sun..Will this amount of sun be enough?
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |