Native Plants
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.
rate this answer
Wednesday - April 14, 2010
From: Valley Center, CA
Region: California
Topic: Propagation
Title: Plants that will grow under a magnolia tree.
Answered by: Nan Hampton
QUESTION:
We live in California near San Diego and have a Magnolia Tree. We have tried to plant many types of flowers around the tree only to have them die. Is there a particular type of plant that we should be planting?ANSWER:
You have discovered for yourself that magnolias are allelopathic to other plants. This means that the magnolia produces chemicals that inhibit the germination of seeds and growth of plants that are potential competitors for its resources. The roots and fallen debris (leaves, flowers, etc.) from the magnolia tree contain substances that limit the growth of other competing species that grow underneath it. In the case of magnolias, the substances are sesquiterpene lactones—costunolide and parthenolide—(see Abdelgalel, A. M. and F. Hasinaga. 2007. "Allelopathic potential of two sesquiterpene lactones from Magnolia grandiflora L." Biochemical Systematics and Ecology Vol. 35, no. 11, pp. 737-742.) A complicating factor is that many plants won't grow in the dense shade created by the magnolia tree—or any other tree, for that matter.
Walnuts trees (Juglans sp.) also have allelopathic effects on plants growing beneath them. The substance produced by walnuts is called juglone. Virginia Cooperative Extension has an article "Trees for Problem Landscape Sites -- The Walnut Tree: Allelopathic Effects and Tolerant Plants" that offers some tips on reducing the effects of juglone on plants growing near walnut trees that could apply to your magnolia. One important tip is to "Regularly clean up all fallen leaves and fruit..., keeping debris away from desired landscape plants." They also list plants that are tolerant to juglone. These, of course, are NOT guaranteed to be tolerant to the sesquiterpene lactones in magnolias, nor are they necessarily native to Southern California (nor, for that matter, are any of the Magnolia species).
I could find no list of plants that are resistant to the allelopathic effects of magnolias. So, my recommendations to you are: 1) keep the debris from the magnolia cleaned up from the area where you want the flowers/plants to grow, and 2) choose native plants that are shade-tolerant. Here are a few recommended shade-tolerant herbaceous plants that are native to San Diego County or an adjacent California county:
Apocynum androsaemifolium (spreading dogbane)
Argentina anserina (silverweed cinquefoil)
Athyrium filix-femina (common ladyfern)
Claytonia perfoliata (miner's lettuce)
Fragaria vesca (woodland strawberry)
Lobelia cardinalis (cardinalflower)
Maianthemum stellatum (starry false lily of the valley)
Polystichum munitum (western swordfern)
Pteridium aquilinum (western brackenfern)
Viola adunca (hookedspur violet)
More Propagation Questions
Tiger lilies for Austin
July 12, 2007 - My dear friend absolutely loves tiger lilies, and I would love to plant some for her, but I wonder if the short winters here in Austin, TX make growing these difficult.. I know little of growing flowe...
view the full question and answer
At what age does Possumhaw (Ilex decidua) begin to flower in Pflugerville, TX?
January 13, 2011 - At what age does a female possumhaw (Ilex decidua) usually bloom and set fruit? Or is there a way to identify the female other than by the presence of berries? I grew a number from seed and want to ...
view the full question and answer
Removal of non-native zoysia grass from Burgettstown PA
September 12, 2013 - What is the most effective method of killing zoysia grass? We bought a house that sits in the center of four acres of mature zoysia. It looks beautiful, however, despite our best efforts at "weeding...
view the full question and answer
Propagating sundrop plants in Dallas
May 18, 2009 - How do I propagate sundrop plants?
view the full question and answer
Transplanting sumacs in Ontario
August 23, 2010 - I live in Aylmer Quebec. I have 10 baby sumac in my back yard and want to transplant them at my cottage in southern Ontario on Lake Simcoe. When can I do this and how?
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |