Killer Trees (black walnut) in my garden area

Robin Posts: 1
edited November 2020 in Pest & Weed Problems/Solutions

Just before winter we moved into our first (and hopefully forever) home. We have 1 acre on which to raise chickens, grow fruit trees, berry bushes, and put in some nice raised garden beds with no bottoms -- I want the worms to have access to my beds. However, after we moved I began paying attention to the trees (I know, too late). I noticed that one of our trees has what I think is mold around the base of the tree, about a foot high, both white & black coloring. Of course I don't want to use harsh chemicals to treat it, and in the process of looking for a solution online, I identified the tree as a black walnut, and then realized that it is NOT a tree to have near a garden due to the juglone that every part of the tree releases that either kills or inhibits the growth of many plants -- hence its nickname Killer Tree. Upon inspecting our other trees, I found that we have several black walnut trees spread across the yard. In my limited research, I found that it is ideal to keep a distance of 50-80 feet between a black walnut tree and a garden, which rules out my whole garden & compost area! Unfortunately, I feel it best to chop down the black walnut trees (I am also very allergic to them!), but even then, the roots are still in the ground and can take several years for all the remaining juglone to be released.  I am so eager to start my little mini homestead and get started being self-sufficient, but this juglone seems like it may set me back a few more years. Is there anything I can do (eg. any plants that will quickly help absorb juglone) to speed this up so I can get gardening? ALL ideas are greatly appreciated!

Also, do you have any advice about the mold? After chopping down the tree, is it safe to plant anything nearby due to the mold? Will it spread?

And, finally, if you are aware of any other trees, shrubs, or plants to look out for that in some way inhibit a garden, I would love to know what they are and why!

Thanks everyone!


  • chimboodle04
    chimboodle04 Posts: 286 ✭✭✭

    We had a black walnut next to where we planned our garden. While we did end up taking it out (there were other problems with its placement, not the least, its proximity to the neighbors garage), but we were also left with the roots. We ended up building raised beds to solve most of this and they have performed wonderfully. Since the tree was gone, we didnt have to worry about any roots growing up into the beds (which they may if you have live trees, so plan some sort of barrier so they cannot get into your garden soil). One of the beds close to where the black walnut was was going to be a bed for our asparagus. We didnt want this to be raised up from the ground level (our winters can get very cold and the plants would die...) so my husband actually dug out the bed there to a depth of two feet and we added all fresh soil. Wouldnt recommend doing that all over, but for that bed it worked well. Something else to do is to plant juglone tolerant crops in the beds where they will most likely come in contact with the black walnut roots. There are many lists available online to find which plants can handle it and which ones cannot. Good luck!!!