I thought I could compost leaves and debris from my black walnut tree in the...

Asked May 22, 2014, 9:59 PM EDT

I thought I could compost leaves and debris from my black walnut tree in the plot whereI had my first vegetable garden last year. Cleaning it out this spring, it smells so bad, kind of like ammonia. My neighbor said the black walnut poison the soil but it was all debris, no actual nuts. Is it okay to grow vegetables in that spot again or did we poison the plot?

Hennepin County Minnesota black walnut

5 Responses

Oh, boy! ALL parts of black walnut & butternut trees contain juglone which inhibits growth in certain plants such as tomatoes, peppers, egg plant and some others. Here is a link giving much more information including some plants affected by it. I would move your vegetable plot off this site for several years until the juglone dissipates.
http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/toxicity-of-black-walnuts-towards-other...

I was afraid of that, the plot gets the best sun and is away from the tree. Do you think I could take out about a foot of soil, then make it a raised bed?

That should work and a few years you will be able to use it again.

To clarify, if I take about a foot of soil out, then add new soil and make a raised bed in the same plot, would I be able to still have a vegetable garden in the same spot? Could there be any harm to eating veggies grown for this plot or is it that they just won't grow there now? Thank you for your help! Sincerely, the beginning gardener with a nightmare walnut tree...

To be clear, there is no harm to you by eating vegetables grown in soil containing juglone (we eat black walnuts). Juglone restricts plane growth in some plants. So, there isn't any problem in installing a raised bed in this area, go for it.