Hi,
I'm working on my food forest. I've run into a bit of a detour. We have two giant black walnut trees. I'm finding out about black walnut toxicity. The roots (and leaves/nuts) give off a substance that is toxic to several other plants. So far, I'm seeing the effects on tomatoes and rhubarb.

Does anyone have any experience with growing figs in ground near black walnuts? There are also mixed messages depending on which university extension service you go to. I'm thinking of just making sure I plant everything as far from them as possible. It's less convenient, but safe.

Oops, I did find a post when I did a Google search, just not with the forum search. Anyone have any additional experience?

http://figs4funforum.websitetoolbox.com/post?id=5789023

Hi Jeff. I have a little grove of black walnut trees. I was told by the tree nursery people  not to plant anything within 25 feet of the walnuts  due to toxicity.

You may want to try the search button on the upper right........being that its late on the east coast it may take another day for someone to answer....good Luck.

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Armando from California

Hi Jeff,
I have no idea if this will work or not, but I recently watched an episode of Nature called "What Plants Talk About"...fascinating stuff.  http://www.pbs.org/wnet/nature/episodes/what-plants-talk-about/video-full-episode/8243/
Enjoy the whole episode, but around minute 28 they talk about spotted knapweed and how it exudes a chemical that pushes back other plants so that it can take over an area.  They found that the oxalic acid exuded from lupine roots actually nullifies the chemical from the knapweed roots and allows the grasses that normally don't do well by knapweed to do okay.  I tried doing some searches to see if lupines will grow near black walnuts, but found nothing.  If it works you'll get the benefit of beautiful flowers that fix nitrogen.  If you want to try and need any lupine seeds I think my plants haven't dropped all their seeds yet.  Just drop me an e-mail.

Thanks, Greg. I think I may have some lupine seeds I didn't plant. I'll check. I wonder if they neutralize juglone? I do love lupines. I knew about the toxicity but forgot to check if it affects rhubarb. I'll be digging that bed up and moving it. I just wish there were definitive answers. I bought two apricot trees. One site says that prunus spp. are fine, and another says apricots are susceptible. I guess I'll revamp my layout and plant them somewhere else. I've scored several fruit trees and berry bushes at the local garden center clearance.

I tested out the area in my backyard that has walnut trees.
Fig trees seem to be stunted, slow growth, when near walnut trees.
one fig plant died, one stunted and I moved it to other location where it is now doing fine,
another still among the walnuts, thought it was dead but it came up from the roots, not one of my favourites so I am leaving it there to see how it does.

5 years ago the farm I was living on had 5 B Walnut trees in the yard between the two buildings we were using as homes. I did a fair amount of research on juglone - the substance released by BW trees that causes so much trouble. There are a number of lists of plants tolerant of juglone but I've not seen one that included figs. The trees affected were much further away then the online articles said they should be. We had new plants we situated as far away as 100 feet that just suffered and finally died.

Black Walnuts are incredible timber trees - my favorite American wood for furniture and panelling. The problem is they are the last tree to leaf out and the first to drop their leaves. Their nuts will fall and dent shed roofs and cars and their sap will eat right through the paint on your car and I have yet to find any solvent that will remove their sap from car paint. The nuts are quite popular for deserts and candies in the south but you have to run over the darn things with the tractor to get to the meat.
The Am. Indians used the hulls of the nuts for dye and my x used to wrap eggs in leaves then boil them to make really cool Easter eggs.
As far as figs go - all mine were in pots but from everything I've experienced with BW I wouldn't put a fig tree in ground within a 100 feet of a large BW tree.
An interesting factoid -- when I was younger these trees were so expensive due to their extremely high quality wood that people cut them down and stole them from folks yards. Individual trees could easily fetch 10 grand at a saw mill and during the period that this wood was so sought after many were planted in areas adjacent to other sensitive trees causing major issues as the BW grew and released more jug lone. Eventually the timber market moved on to lighter colored woods and the walnut is no longer as popular. As youngsters in science class we took shell hulls, etc. and soaked them and then treated seeds with that fluid to show how juglone inhibited germination. It's a pretty good defense mechanism to keep from being crowded by other species.
I doubt figs have much resistance  to juglone as they did not evolve in contact with the BW. I had trouble finding any direct evidence however, even though I tried a number of southern universities.
That's all I got. Good luck.

I've got wild mulberry,wild cherry,apple,plum,and pear trees growing within 50' or less of 0.75'-1' trunk size black walnut trees with no ill effects of growth or fruit production that I can see as compared with fruit trees at further distances.

Good info. Thanks. I have a real love/hate relationship with these trees. I guess I'll just have to work around them.