Question:
We've just purchased a new home and I would like to have
a garden next summer. But many people have told me I will never be able
to have one with all the black walnut trees in my yard as they poison the
soil with juglone. They have all suggested that I cut down every one of
the trees. They are very fine nut producers. My question is this: How
many feet away does a walnut tree have to be from the area designated as
a garden area so that the poisoning effects will not interfere with my
garden. Also, if I have to cut down some of the trees (I have 40 trees
in various locations) what time of the year is this to be done ideally?
Replies:
I do not have references in front of me on the effecfts of walnuts on other
plants, but I can tell you from experience that walnut trees in the yard
where I grew up seemed to have little effect on nearby flowers and fruit
trees; however there were no garden vegetables in that part of the yard. Two
large walnuts are still growing there and there is a wonderful mixed
domestic and wild flower garden, apple and cherry trees, etc. I suggest that
as for any trees any possible effects extend no farther than the drip line,
that is the effect of shade and root competition which extends out from the
trunk about the width of the crown.
Nature black walnut trees can be very valuable. You may find that if you
cut down the trees to setup a garden you may in the future regret your
decision.
I would suggest contacting your local county extension agent (in the
government listings for your county) and asking who you might speak to about
the black walnut trees. A local extension agent or forester should be able
to provide information to you about the value of the walnut planting based
on age of the trees and their condition. Please write again if you are
unable to locate information. Once you have the information you will then
be more able to make an informed decision about growing vegetables for food
or the trees for their beauty and investment potential.
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