Bobberman
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How bad is the black walnut tree for the garden?

You better look twice before putting you plants near a Black Walnut tree or even using some ogf the leaves becase of a chemical juglone! I am even watching the green shells now. I have two small new trees n my garden about 8 feet tall which are coming down quick!!
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https://ohioline.osu.edu/hyg-fact/1000/1148.html

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rainbowgardener
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I think it is over rated. I have a huge old black walnut. Right under it I planted a viburnum, a hydrangea, and a raised bed full of shade flowers. Maybe the raised bed helps protect them, I don't know, but it is only raised a few inches. The viburnum and hydrangea are in the ground, all nestled amongst the black walnut roots. Everything is doing fine. Can I prove that they might not have been a little bigger or something without the walnut? No, but they appear to be thriving, everything blooms, etc. They've been there at least six years now.

Don't get rid of your walnut trees unless you really don't want them!

DoubleDogFarm
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I'll second what Rainbow is saying.

I have many fruit bearing bushes under two black walnut trees. My black walnut trees are about 10 years old, but I see no ill effects.

Eric

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lorax
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Depends entirely on what you plant under the walnuts - friends of mine have Juglans neotropica (Andean Walnuts) that are about 50 years old, and they've got thriving stuff underneath - Anthurium, Caladium, Fuchsia, etc.

Juglone does seem to inhibit grasses and dandilions, though. :shock:

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jal_ut
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Any tree near your garden will compete with your garden plants for sunshine, water and nutrients. I had to move my garden over 60 feet to get away from some hybrid poplars.

With walnuts there is supposed to be some allelopathy going on. This affects some plant species more than others though.

[url=https://pubs.ext.vt.edu/430/430-021/430-021.html]Here is some good info.[/url]

DoubleDogFarm
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Any tree near your garden will compete with your garden plants for sunshine, water and nutrients. I had to move my garden over 60 feet to get away from some hybrid poplars.
I will second what James is saying, also add to that grass and weeds.
Juglone does seem to inhibit grasses and dandelions, though
Lorax, Under my black walnuts and english walnut, I have no dandelions, but a full carpet of grass. Maybe with a more mature walnut grove, shade and leaf litter is part of the equation.

Eric

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lorax
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DDF, I'd say it probably depends on the grass. The Andean walnuts seem to inhibit native grasses (which tend towards the highly vigorous nearly invasive), but allow beautiful carpets of moss when they occur in wild forest habitats. However, another friend successfully grows blue fescue under her Andean walnuts....

Bobberman
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The juglone is supose to be really bad for Tomatoes and a few vegs! Some things thrive in bad places!

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lorax
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Yes, but who in their right mind would grow tomatoes in the shade of any tree, walnut or otherwise?

Bobberman
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ME would! I put a bushel of walnuts in a garden area 7 ears ago and a few trees came up so I left them grow now to about 10 feet and trimmed them to make shade for some cropsbut now they will be cut down. But the leaves are also bad and I would assume the black green shells are really bad!

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Gary350
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Black walnuts will keep away ants and bugs and even termites. The old people collect black walnuts to dump around the house and under the house to keep ants and termites away. I have a 50 ft tall black walnuts tree that causes me no problems at all other that 2 bushel baskets of walnuts scattered all over the place.

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rainbowgardener
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Juglone definitely does not inhibit english ivy anyway. (Not too surprising since nothing much does; it's difficult to kill even with Round up.) There was a bunch of ivy at the base of my walnut tree that was climbing up it and threatening to smother it. Last spring I pulled it all off the tree and away from the base of the tree. Otherwise I think the ivy might have won.

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applestar
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If I had the space, I would grow some black walnuts -- there are many time-honored uses.... But probably not anywhere near the garden.

However, for folks with existing trees, I remember an old thread in which Veg's that can be grown and not grown near black walnut trees were thoroughly explored.

I took a wood carving class in College and the prof had a whole stack of seasoned rough-hewn blocks of black walnut wood to choose from. They are beautiful wood.

Bobberman
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I love walnut trees in the right place. Most of you probably have never seen a butternut tree. We had several near my home till the Latrobe Brewery cut them down. The nuts are longand more oval that round. The nuts are strong tasting but very good! About 4 years ago I put some wood chips near my zucks and they died. I always wondered why but I am thinking the chips were walnut!

Green Lab
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We have a big plastic blue barrel that we used to store black walnuts. If we clean it out, what should we use to get it clean? So we can make a organic fertilizer tea so the juices from the walnuts don't hurt our fertilizer.

Little Homestead
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Butternut is closely related to walnut...in fact the botanical name of both starts with Juglans. Walnut is Juglans nigra and Butternut is Juglans cinerea. They both contain the juglone toxin.

Every part of the tree contains this chemical, including the roots which spread out much farther than the spread of the branches. So plants that are susceptible to this toxin will be affected further out from the tree than most people realize.

There are quite a few shrubs that do well around walnuts. If you check online there are some sites by Cooperative Extension agencies that list what plants do well around these trees.

Many vegetables do not do well, however.

erlyberd
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A black walnut tree in good condition is like money in the bank or money for your garden as the lumber can be worth some bucks!$$$

But I agree any tree is just competition and should be removed if anywhere near your garden.



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