What Grows Under A Black Walnut Tree - Knowledgebase Question

Alexandria, VA
Avatar for sebbie10
Question by sebbie10
April 13, 2001
I have a black walnut tree in the back yard. I know that the roots are poisonous to many plants, and I'm limited in what will flourish or die in that soil. I have a hard time growing a lot of things. I once saw a list (but since lost it) of annuals and perennials that do ok or well near a black walnut tree. Do you have such a list? Many Thanks


Image
Answer from NGA
April 13, 2001
Black walnut (Juglans nigra) has a reputation for being allelopathic--that is, for inhibiting the growth of other plants. Small amounts of a substance called juglone are released by the tree roots, but a far greater amount of this growth-inhibiting chemical is found under the canopy of the tree.

Some plants that are tolerant to juglone include: arborvitae, cedar, catalpa, clematis, daphne, elm, euonymous, forsythia, hawthorn, hemlock, sycamore, astilbe, begonia, bellflower, orange hawkweed, hosta, pansy, phlox, marigold, primrose, snowdrop, sweet woodruff, trillium and zinnia. Since your walnut tree is there to stay, try to plant one of the less-susceptible plants in the vicinity of the trees roots or canopy.

Avoid plants that are sensitive to juglone, including apple, blackberry, pear and blueberry, asparagus, cabbage, eggplant, pepper, potato and tomato. Landscape plants sensitive to juglone include azalea, birch, honeysuckle, hydrangea, larch, lilac, magnolia, maple, pine, potentilla, rhododendron, spruce and viburnums.

You must be signed in before you can post questions or answers. Click here to join!

« Return to the Garden Knowledgebase Homepage

Member Login:

( No account? Join now! )

Today's site banner is by IrisLilli and is called "Purple Crocus Mix"

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.