Black Walnut Kill

Asked July 31, 2019, 2:50 PM EDT

I've replanted my yard to Kentucky Blue Grass but would like to add a second and third grass if possible that won't be killed by the black walnut. Can you recommend a hardy grass for Minnesota that can stand up to Black walnut?

Ramsey County Minnesota black walnut tree

1 Response

Thanks for the question.

Well to be honest, it will be a challenge. Juglone is toxic to many plants. This toxicity may exist up to fifty feet or more from the tree itself. With respect to growing grass, there are different opinions. Some gardeners assert that Kentucky Bluegrass and Tall Fescue can grow. Others recommend that no grass will survive. Any growth that might occur, however, will require constant diligence on your part. Keep in mind that under a walnut tree there will be considerable shade and Kentucky Bluegrass does not tolerate shade well. The soil composition will also influence turf growth. Your situation might be one where you should try growing grass (would not recommend blue grass but either tall fescue or creeping red fescue) and see what happens. I have often found that what is recommended from what will work requires simple experimentation. The following may help you in selecting possible grass seed:

https://turf.umn.edu/news/can-we-use-tall-fescue-lawns-minnesota

https://turf.umn.edu/news/finding-right-grass-seed

I don’t know how much time and effort you want to put in trying to grow the grass under the tree and endure the high yearly maintenance. Mulch might be an easier substitute. Something other than grass should also be considered. See:

https://www.mortonarb.org/trees-plants/tree-and-plant-advice/horticulture-care/plants-tolerant-black-walnut-toxicity

https://homeguides.sfgate.com/grow-under-walnut-tree-69873.html

Good Luck!!