It appears you do not have Javascript enabled in your browser. Javascript must be enabled for our website to display and function properly.
Free Seeds On Online Orders Over $50

Companion plants that tolerate black walnut tree toxicity

Jan 24, 2013 -
   
  Companion plants that tolerate black walnut tree toxicity
Glory of the Snow (Chionodoxa forbesii) is a fall-planted bulb that grows happily under any walnut tree.
 
   

Walnut trees are fruitful and beautiful. I love to sit in the shade of one of my walnut trees and look out over the sloping garden. In our new video Tricia shows you how to care for and prune walnut trees.

walnut orchard

Walnut trees definitely like their own space, and can be bad neighbors to certain plants. Find out the best companion plants for walnuts.

Black walnut tree toxicity

Black walnut trees load their roots, buds, and nut hulls with the juglone toxin (leaves and stems have smaller amounts of juglone). The toxin seeps into the soil and susceptible companion plants will turn yellow, wilt, and sometimes die.

But wait, you say, I don’t have a black walnut tree. Actually, most walnut trees are grown on black walnut rootstock these days, therefore the root system is likely to be rich in juglone. The soil under the canopy of the tree will have the highest concentration of juglone due to the combined effects of the roots, along with fallen leaves, hulls, and shells that are lying on the ground. Picking up this litter is good “orchard sanitation” for many Integrated Pest Management reasons, including decreasing the amount of juglone.

franquette walnuts

Companion plants for black walnut trees

Purdue University has informal lists of plants that tolerate juglone and those that are sensitive to it. Choose from the following list for best results in planting near black walnut trees or walnut trees grown on black walnut rootstock. Follow these guidelines for planting within the dripline of the tree and, according to the University of Wisconsin, up to 50’-80’ from the trunk. Naturally you need to consider the sun and shade requirements of the plants, as well.

Vegetables: lima bean; snap bean; beet; carrot; corn; melon; onion; parsnip; squash.

Fruits: black raspberry, cherry.

Landscape plants: arborvitae; autumn olive; red cedar; catalpa; clematis; crabapple; daphne; elm; euonymous (burning bush); forsythia; hawthorn; hemlock; hickory; honeysuckle; junipers; black locust; Japanese maple; maple (most); oak; pachysandra; pawpaw; persimmon; redbud; rose of sharon; wild rose; sycamore; viburnum (most); Virginia creeper.

Flowers and herbaceous plants: astilbe; bee balm; begonia; bellflower; bergamot; bloodroot; Kentucky bluegrass; Spanish bluebell; Virginia bluebell; bugleweed; chrysanthemum (some); coral bells; cranesbill geranium; crocus; Shasta daisy; daylily; Dutchman’s breeches; ferns; wild ginger; glory-of-the-snow; muscari (grape hyacinth); grasses (most); orange hawkweed; herb Robert; hollyhock; hosta (many); hyacinth; Siberian iris; Jack-in-the­ pulpit; Jacob’s ladder; Jerusalem artichoke; lamb’s ear; leopard’s bane; lungwort; mayapple; merrybells; morning glory; narcissus (some); pansy; peony (some); phlox; poison ivy; pot marigold; polyanthus primrose; snowdrop; Solomon’s seal; spiderwort; spring beauty; Siberian squill; stonecrop; sundrop; sweet Cicely; sweet woodruff; trillium; tulip; violet; Virginia waterleaf; winter aconite; zinnia.

Plants that are sensitive to black walnut tree toxicity

Vegetables: asparagus, cabbage, eggplant, pepper, potato, rhubarb, tomato.

Fruits: apple, blackberry, blueberry, pear.

Landscape plants: black alder; azalea; basswood; white birch; ornamental cherries; red chokeberry; hackberry; Amur honeysuckle; hydrangea; Japanese larch; lespedeza; lilac; saucer magnolia; silver maple; mountain laurel; pear; loblolly pine; mugo pine; red pine; scotch pine; white pine; potentilla; privet; rhododendron; Norway spruce; viburnum (few); yew.

Flowers and herbaceous plants: autumn crocus (Colchicum); blue wild indigo (Baptisia); chrysanthemum (some); columbine; hydrangea; lily; narcissus (some); peony (some); petunia; tobacco.

Field crops: alfalfa; crimson clover; tobacco.

Tip: This does not mean you can’t compost black walnut leaves. According to Ohio State University Extension, “walnut leaves can be composted because the toxin breaks down when exposed to air, water and bacteria. The toxic effect can be degraded in two to four weeks.” If you do compost the leaves, put them in a separate compost pile and do not spread the resulting compost on plants that are on the sensitive list.

For more information: The go-to book for anyone growing nut and fruit trees in California is the UC Davis publication, The Home Orchard.

Add some walnut trees to your property and create a beautiful landscape with these companion plants that tolerate toxicity.


Categories: Nut Trees, Edible Landscaping


Tere Says:
Oct 28th, 2013 at 12:03 pm

Charlotte, I have lots of black walnut stumps that I would like to use for edible mushroom cultivation. Specifically, Chicken Mushroom and King mushrooms Is it safe or does the toxin continue into the mushroom?

Stephanie Brown Says:
Dec 20th, 2013 at 10:25 am

Tere, Juglone is present in every part of the plant so unless someone eating the mushrooms is allergic to walnuts it should be just fine. Juglone is a natural antimicrobial agent so I’m not sure if the mushrooms would take right away, but I found no research that said not to use them. Hopefully that helps.

Katie Says:
Feb 10th, 2014 at 12:12 pm

My son wants to make cutting boards using walnut.  Can the sawdust be composted - or would we be better off making a separate compost pile for this?  also, does the wood pass along any toxicity in the cutting board?
Thanks.

Stephanie Brown Says:
Feb 10th, 2014 at 4:25 pm

Hello Katie, Yes I would make a separate compost pile with walnut saw dust and don’t use it on sensitive plants. The composting process will reduce the juglone quite a bit but a might release a little bit still. The cutting boards will be beautiful and safe. You get quite a high dose of juglone from eating walnuts (English walnuts have less than Black walnuts). In fact, in the case of pecans, the juglone content of the nut is two to three times higher than the trunk.

Sandra Says:
Feb 25th, 2014 at 2:25 am

What about quinoa? thanks

Sanda anderson Says:
Feb 25th, 2014 at 8:45 am

Hello Charlotte,
Would quinoa tolerate walnut toxicity? Thanks in advance

Stephanie Brown Says:
Feb 25th, 2014 at 12:44 pm

Hello Sanda,
I was unable to find any research that said it grew under walnuts or it didn’t. I’d say it’s worth a bit of trial and error to see. If lambsquarter grows under walnuts than the quinoa would do well since they are very close relatives.

Sarah Says:
Mar 10th, 2014 at 12:37 pm

I can’t find hazelnut or filberts on any of the lists, as companion or sensitive. We have a couple black walnuts on our property and would love to add a couple of native hazelnuts. But it makes no sense if they will die. Do you have any useful information on this?

Stephanie Brown Says:
Mar 11th, 2014 at 8:33 am

Hello Sarah,

According to Penn State American Hazelnuts (Corylus amaricana) the native hazelnut are on the tolerant of juglone list. http://extension.psu.edu/plants/gardening/fact-sheets/trees-shrubs/landscaping-and-gardening-around-walnuts-and-other-juglone-producing-plants

Vicki Nash Says:
Mar 27th, 2014 at 8:43 am

I need to know what herbs specifcally mint or spearmint & dill and parsley

Stephanie Brown Says:
Apr 8th, 2014 at 10:41 am

Hello Vicki,
Yes, mint is on the tolerant of juglone list. I haven’t seen dill or parsley on either list. Juglone toxicity tolerance or sensitivity is an active area of study. All that to say, for many plants it’s just not known.

doot trolz Says:
Apr 23rd, 2014 at 7:59 am

we have deer and black walnut.  will lavender, gallardia, salvia, yarrow, and soapwort grow under black walnut?  The deer don’t eat those.  We have cone flowers, black-eyed susans and vinca, both walnut and deer resistant but would like to try something new. love this column!

Stephanie Brown Says:
Apr 23rd, 2014 at 9:42 am

Hello Doot,

Yarrow is known to be resistant to juglone. Lavender, gillardia, and salvia don’t appear on either list, so I’d say they’re worth a try. Some other juglone and deer resistant perennials I found are bluebells (Endymion sp.), Jack-in-the-pulpit, and daffodils. Good luck!

doot Says:
Apr 24th, 2014 at 7:23 am

Thanks so much!  We’ll give ‘em a try and let you know!

kevin prendergast Says:
Apr 27th, 2014 at 10:18 am

can i plant a decorative dappled willow tree near my 36 inch diameter black walnut tree ?  dappled willow would be planted 60 feet distance from walnut tree in a slightly raised bed.

Jackie Says:
Apr 28th, 2014 at 5:26 am

Daughter wants to know if lavender will grow near a walnut tree. Thank you in advance on your responding to this request.

Stephanie Brown Says:
Apr 28th, 2014 at 7:56 am

Hello Jackie,

Lavender isn’t on the sensitive or the tolerant list. Juglone sensitivity is an ongoing study, so it’s not known. I’d say get one plant and see if it does well.

Stephanie Brown Says:
Apr 28th, 2014 at 8:07 am

Hello Kevin,

Willows are on the tolerant list so it should be fine.

Molly Says:
May 17th, 2014 at 8:30 pm

Are there any rhododendrons that can tolerate black walnut? Mine has slowly killed off two! I do have good luck with peonies, hosta, ferns, and Japanese maples!

Stephanie Brown Says:
May 19th, 2014 at 9:05 am

Hello Molly,

Unfortunately, I don’t know of any rhododendrons that are tolerant of juglone. Rhodies are on the sensitive list.

Steve B Says:
Jun 19th, 2014 at 7:56 am

Love this article and the comments: really helpful.  We recently had a 75+ year Blk Walnut taken down and stump ground out and are looking to put a new tree in close proximity.  Sounds like Japanese maples and rosebuds are tolerant, but our wish list for new trees also includes dogwood and tricolor beech.  Has anyone had any experience with these and how they might tolerate juglone in the residual rotting root systems?  We are SE Pennsylvania area, and are looking forward to no longer having walnuts hit us and our cars in the nearby driveway.

Jeffrey Lodginski Says:
Jul 1st, 2014 at 11:23 am

Will healthy ferns about 4 to 5 feet tall survive lining near a black walnut tree?

Stephanie Brown Says:
Jul 2nd, 2014 at 10:30 am

Hello Jeffrey,

Yes, ferns have been observed to be tolerant to juglone.

Stephanie Brown Says:
Jul 2nd, 2014 at 10:34 am

Hello Steve,

Dogwoods are considered tolerant. I haven’t seen beech on one list or the other. The juglone will persist in the soil for a while as the roots decompose in the soil.

Karen Says:
Jul 23rd, 2014 at 4:26 pm

Hello I am wondering if aronia is tolerant of black walnut as well as the s. Nigra species of elderberry?

Suzanne at Peaceful Valley Says:
Jul 25th, 2014 at 12:25 pm

According to information I found on the internet, Aronia is highly sensitive to juglone and should not be planted by a black walnut. I have found information on the Virginia Cooperative Extension (http://pubs.ext.vt.edu/430/430-021/430-021.html) that says elderberry is tolerant to growing near a black walnut.

Mary Says:
Jul 28th, 2014 at 8:09 pm

Wondering about herbs like basil, tarragon, oregano and lemon thyme? Will they be ok under the tree? Planted before i realized it was a black wanut tree in my new yard!

Suzanne at Peaceful Valley Says:
Aug 1st, 2014 at 11:56 am

I have not found information regarding the herbs you are interested in planting. All the herbs you listed, except tarragon, prefer full sun so planting under a tree may not be the best idea.

Penny Says:
Sep 3rd, 2014 at 11:23 am

Black walnuts are protected trees here, in Los Angeles.  I have one outside my back fence along the street, but it seems to be effecting the bed on the inside of the fence.  I planted pickling cucumbers & cantaloupe and both yellowed & died.  However, 3 rhubarb plants seem to be thriving there.  Odd, since melon is on the tolerant list and rhubarb is on the vulnerable list.

Fred Says:
Sep 16th, 2014 at 6:21 pm

We have many black walnut trees in our yard. In the fall I use the leaves for winter mulch which I remove every spring and pile up in an open area of the garden. I have heard the leaves shouldn’t be used for mulch. This process has been going on for years.

This past spring I had some extra seed potatoes left over so I put them into the pile of black walnut leaves. Over the course of the summer I noted that the potatoes in the black walnut pile were sending up very vigorous plants. I dug the potatoes today and I have never seen such big and so many potatoes from single plants.

I find this strange when black walnuts are supposed to be toxic to potatoes.

Margaret Smith Says:
Sep 24th, 2014 at 6:09 pm

Hey, I’ve read some of the comments about black walnut, and would like to add mine.  We raise grass fed beef and have noticed that although grasses such as fescue will grow under these trees, cattle don’t like to graze it under the trees as far out as the branches.  Also, we are planning a test plot of cereal rye in our hay field, and it has walnut trees growing along the edge of a one acre section where grass is thin.  I’m pretty sure it isn’t due to the trees, since grasses are growing under them on other parts of the farm.  This area is acidic, and I think cereal rye is happy with that.  If I get a chance, I’ll write back and let you know the results.  I’m in VA, so think I can get a pretty good stand established before really cold weather sets in.

Elizabethe Walton Says:
Oct 3rd, 2014 at 7:22 am

We grow horseradish in an old tire. This keeps the root curling around and around inside the tire, and it has not been invasive, even though it is in the middle of our regular garden. It has been three years now, with no sign of invasiveness. It also makes it easier to harvest the root, to divide it if you want to do so, and to make sure you get all the roots if you want to remove it elsewhere.

Suzanne at Peaceful Valley Says:
Oct 7th, 2014 at 11:47 am

Not sure why the potatoes are growing in the pile, possibly lower levels of the juglone in the leaves.

Kim Ziccardi Says:
Jan 15th, 2015 at 8:42 am

We were able to grow pickling cucumbers in a large container: gave them a trellis, and they thrived quite well. This was about 15 feet away from a black walnut tree in Upstate New York.

Anita Braden Says:
Feb 7th, 2015 at 3:49 pm

Can I grow PawPaw trees near my black walnut trees?

Suzanne at Peaceful Valley Says:
Feb 13th, 2015 at 11:51 am

The sources I viewed did not say anything about pawpaws under black walnut trees. You might seek out the advise of your local Master Gardener in your area. They might have a better idea.

JoAnn Says:
Feb 14th, 2015 at 9:17 am

Pawpaws are shown as tolerant on several lists that I have.  Someone earlier questioned Japanese forest grass, mine did not do well in a walnut shade garden, hosta, astilbe and ferns perform spectacularly.  Have also not had any luck with coral bells, which are listed as tolerant.

Barbara Says:
Mar 8th, 2015 at 11:55 am

Will the soil rejuvenate if I take out several small black walnut trees that are growing on the outskirts of my garden?  How can I help the soil enrichment process?

Suzanne at Peaceful Valley Says:
Mar 25th, 2015 at 1:18 pm

The toxic effect from the black walnut roots can persist until they are decomposed, could be up to 4-5 years, depending on the rate of decomposition. Try planting a cover crop in the area to improve the soil, avoiding crops with clover or alfalfa, they seem to be more sensitive.

Ellen Says:
Apr 1st, 2015 at 4:57 pm

I know someone already asked about crabapple being resistant to juglone the response said that according to the U of Minn, it is resistant. However, I read on the University of Wisconsin Extension website that crabapple is sensitive to juglone. https://hort.uwex.edu/articles/black-walnut-toxicity

I’m confused. I have to take out two ailing black walnut trees in the right-of-way in front of my house and I’d like to replant with crabapples. Will they die?

Suzanne at Peaceful Valley Says:
Apr 9th, 2015 at 11:33 am

Per my previous comment about black walnuts, the toxic effect can remain in the roots until they have decomposed, which could take 4-5 years. I would probably not plant in the area of the black walnut trees for a couple of years.

walter jones Says:
Apr 17th, 2015 at 5:37 am

will ornamental grasses grow under walnut trees …

also, how far away from the walnut tree would be ok for a cherry (fruit bearing) tree ?

thanks

Linda Saunders Says:
Apr 19th, 2015 at 12:56 am

Hello, I have a well established Black Walnut Tree set in a smallish lawn.  We planted Euonymus all around the edge of this area and some plants are actually under the canopy. Some plants were small leafed and others were the larger leaf variety, and weirdly all the small leafed ones died leaving the others to thrive!!  My red Lilac is dying a lingering death and want to put it out of it’s misery;  I notice that you mention Viburnum in both lists.  Do you think a Viburnum Tinus will survive.  We live in South West France and they love our climate.  I have enjoyed reading everyone’s comments, opinions and experiences, so merci beaucoup a tous!

Steph Says:
Apr 19th, 2015 at 6:59 pm

Two questions:

Are Crape Myrtles resistant to juglone?

Also, my black walnut tree is located at the lowest point of my backyard, which is shaped like a bowl. If I plant white pine and/or crape myrtles along the rim of the bowl- at a higher elevation than the black walnut, can I successfully plant them about 40 ft away?

Suzanne at Peaceful Valley Says:
Apr 23rd, 2015 at 1:36 pm

Walter, Not sure what grasses you are planting, but try the link in this blog for a list of plants. So cherries should be ok, but plant far enough away, well past the drip line of the walnut tree.

Suzanne at Peaceful Valley Says:
Apr 23rd, 2015 at 2:02 pm

Linda, try checking the link we have provided to see if the Viburnum is on the list of tolerant plants.

John Wickens Says:
Apr 25th, 2015 at 9:51 am

I read somewhere that the toxicity affect of the walnut will be worse in a clay or poorly drained soil than it is in a sandy loam (well drained). I have a very sandy soil & can verify that tomato, rhubarb, rhododendron, silver maple white birch, white spruce & apple do not survive near black walnut. Cedar, white elm, raspberry, & lilac do.

Kate Wheeler Says:
May 5th, 2015 at 9:19 am

I have a yellow peony tree planted under my black walnut and it is hale and hearty, my problem is the tiger lilies planted near by which don’t do well but come back in abundance each spring and die back mid summer foliage and all.  I have purchased some tolerant plants and wonder if I should relocate the tiger lilies. Not sure if it’s a juglone problem or too much shade…any ideas?

Suzanne at Peaceful Valley Says:
May 11th, 2015 at 12:01 pm

All I have read about the tiger lily is that they may like moister soil than what you are providing and they like to have their “toes” cool in the shade but plenty of sun on the top growth. So it sounds like they are probably not getting enough sun and maybe not enough water.

philip Says:
May 15th, 2015 at 7:01 am

Do other walnut trees have the juglone problem? I cannot confirm what type of walnut trees I have, but it takes a hammer to crack them open. They grew wild out on my Uncles farm in Iowa and I want to plant fruit trees….apples near them if possible.

Suzanne at Peaceful Valley Says:
May 15th, 2015 at 10:28 am

Actually, most walnut trees are grown on black walnut rootstock these days, therefore the root system is likely to be rich in juglone. Apples are sensitive to juglone so make sure you plant them far away from the walnuts.

James Williams Says:
May 16th, 2015 at 10:40 pm

Wanting to find out if Schisandra is okay with walnut I know grapes are but don’t want to risk my Schisandra plants without finding out first ?

Suzanne at Peaceful Valley Says:
May 18th, 2015 at 10:44 am

James, I have not found any information on Schisandra sensitivity to juglone. If you have a Master Gardener in your area ask them if they might know.

Tania Says:
May 18th, 2015 at 2:10 pm

I read somewhere that certain Magnolia trees are able to live with black walnut trees but now I can’t find that reference. We live in zone 6b (Ontario) do you have any recommendations for either Magnolia trees or other flowering trees that are tolerant? We have 4 large walnut trees surrounding our property. Thanks

Suzanne at Peaceful Valley Says:
May 19th, 2015 at 12:11 pm

I found this species, Magnolia soulangiana, in an article that states it is sensitive to juglone.

Bree Says:
May 31st, 2015 at 2:04 pm

Has anyone asked if grapevines are resistant to black walnut? ?

Suzanne at Peaceful Valley Says:
Jun 1st, 2015 at 9:54 am

I did find a source that states that domestic grapes ARE sensitive to juglone. So do not plant within 50 feet of the drip line of the black walnut.

Ironyman Says:
Jun 3rd, 2015 at 9:22 am

I have Black Walnut growing around my long driveway and around the house. Then I have an old pasture that I plant in. Been careful to keep my garden, blueberries, Pear, apple, peach trees and such at least 80 feet away from any black walnut. I’m trying to create a wild life habit. Food for them and me. What about other trees that have Juglone? I guess most nut trees will have some? I’ve put out some Chestnut and now have some Pecans to plant. Will juglone sensitive trees grow around these other types of trees? Maybe they need not be as far way?

Suzanne at Peaceful Valley Says:
Jun 3rd, 2015 at 10:33 am

The information I found through a google search is that walnuts and hickories produce the chemical juglone. I did not find any information about Pecans or Chestnuts producing juglone.

Gwyn Sylvester Says:
Jun 7th, 2015 at 10:09 am

I have some Chinese Fringe-Flower plants (loropetalum Chinese var. rubrum) that I wish to transplant.  My two giant black walnuts are on the east side of my house and the plants are currently on the north side just around the corner.  They are thriving where they are. Do you think they would be ok with the walnut tree only 20 feet away?

Suzanne at Peaceful Valley Says:
Jun 8th, 2015 at 11:40 am

Gwyn, I did not find any information on whether or not the Chinese-Fringe Flower will tolerate growing near a walnut tree. My only suggestion is to plant some and see if they thrive.

bobby Says:
Jul 9th, 2015 at 5:46 pm

I just took down a 100 year old dying black walnut. I want to plant a Beech tree in its place. Will the beech be tolerant of the toxicity from the old walnut? If not, what majestic trees would you recommend to replant?

Suzanne at Peaceful Valley Says:
Jul 14th, 2015 at 1:39 pm

Bobby, I would check out the links in this article for a list of plants/trees that will tolerate being planted where the black walnut was located.

patti in Wisconsin Says:
Jul 16th, 2015 at 1:15 pm

Will bitter sweet vine tolerate black walnut ?

Kathy Says:
Jul 17th, 2015 at 7:05 am

How far from a black walnut tree can I plant hydrangea?  I have just purchased some new endless summer hydrangeas without checking the tolerant list.  Thank you!

Suzanne at Peaceful Valley Says:
Jul 20th, 2015 at 4:29 pm

Patti, what I have found on the internet is that the American bittersweet vine (Celastrus scandens) is tolerant to juglone from the black walnut roots.

Suzanne at Peaceful Valley Says:
Jul 20th, 2015 at 4:36 pm

Kathy, hydrangeas are indeed sensitive to black walnut trees and also walnuts (which are grafted onto black walnut root stock). You should plant them at least 50 feet away from the drip line of the walnut tree. Also, make sure to keep all leaves, nuts and shells cleaned up as well.

Roxie Schmidt Says:
Jul 20th, 2015 at 9:17 pm

I have spent so much money on hedges only to have half of them die every year.  Finally after going to 3 nurseries, I was asked if we had any walnut trees. We don’t but, the neighbor directly behind has 2. I just purchased 4 coneflower plants in hopes they’ll grow. I not only like them but, need the height.  Please help!!

Suzanne at Peaceful Valley Says:
Jul 21st, 2015 at 9:32 am

Roxie, I would suggest viewing the articles that we have linked in this article for a list of plants that are tolerant to juglone. Or re-vist your local nursery and ask their opinion on what will grow in your area.

ae hughes Says:
Jul 21st, 2015 at 11:01 am

I have just purchased 3 Autumn Cherry Trees and just found out about juglone.  Can you tell me if they will survive planted within 10’ of the black walnut trees?  I have a line of lilac bushes that have finally taken off and seem to be thriving in this vicinity.  Thanks.

Suzanne at Peaceful Valley Says:
Jul 21st, 2015 at 3:31 pm

Ae, I see in one of the articles that cherry trees have been observed to grow near black walnuts. But keep in mind there may be variation between different varieties so I could not say absolutely 100% that they will not be affected.

Raspy Says:
Aug 24th, 2015 at 6:13 pm

I have noticed that in your list, black raspberries are tolerant, but do tolerant plants also assist in reducing juglone proximity from the tree by absorbing it??

If so it may be a way to plant edible raspberries near the tree, and plant more sensitive varieties a little closer to the tree for urban growers with smaller space.

Suzanne at Peaceful Valley Says:
Aug 28th, 2015 at 10:06 am

Raspy, I have not heard of tolerant plants actually reducing the juglone. Improving your drainage will help reduce juglone in the soil and if you really want to plant a sensitive plant by a walnut (or hickory) tree, then planting in a raised bed may be the solution. Just as long as the roots do not penetrate down into the soil where the jugalone is present. Raspberries do not have deep root systems, so they would do fine in a raised bed, or large pot.

Marti Says:
Sep 2nd, 2015 at 7:04 am

Is it better to have a black walnut stump ground out or cut below ground level? I want to plant something that attracts birds and butterflies in its place. WI winters can be rough! Thank you!

Melissa Says:
Sep 2nd, 2015 at 7:20 pm

Are all magnolias sensitive to black walnuts or just the saucer magnolia that is listed?

Suzanne at Peaceful Valley Says:
Sep 3rd, 2015 at 11:43 am

Melissa, I have not found more information about whether it is all magnolias or just the saucer magnolia. You might check with your local Master Gardener for more information.

Suzanne at Peaceful Valley Says:
Sep 3rd, 2015 at 11:45 am

Marti, I would check with an arborist on that type of question. It will take some time for the juglone to degrade in the roots that remain in the ground. So keep that in mind before planting.

Barry Says:
Sep 3rd, 2015 at 4:14 pm

Have Hydrangeas growing like weeds under our Black Walnut.

Marcee Says:
Sep 12th, 2015 at 7:46 am

Does anyone know specifically if the grass “miscanthus sinensis Zebrinus” will survive under a walnut????  thanks for needed info

Kathy Says:
Sep 18th, 2015 at 12:08 pm

We recently cut down a naturally growing black walnut tree.  I had no idea what is was until I asked an arborist.  It was a fairly small clump, but the stump is about 12-18” in diameter.  We transplanted a large barberry bush right next to the stump, and suddenly it looks like it is dying (about 3 weeks later).  Is it from the black walnut tree roots?

Suzanne at Peaceful Valley Says:
Sep 24th, 2015 at 10:01 am

Not sure it really matters in terms of the toxicity of the black walnut. Make sure that you plant something that is tolerant to juglone, since the roots contain it and until they break down the area will remain unusable to plants that are sensitive.

K Says:
Oct 3rd, 2015 at 9:49 am

I had planted a Kwanzan Cherry tree in honor of my father in spring 2014. It bloomed beautifully as it had already set plenty of buds. Was looking forward to seeing it full of blooms this past spring (2015) and got not even one. I have fertilized it with tree spikes. This Cherry tree looks healthy, but was planted only 20-25 feet from my neighbors Black Walnut tree; actually right at the edge of the canopy. My local nursery didn’t think it would be a problem being near the black walnut but now I’m not sure if it’s the black walnut or that it’s just a new planting. What do you think? All the postings have been very helpful. Thanks!

Suzanne at Peaceful Valley Says:
Oct 5th, 2015 at 10:51 am

K, every thing I have read about black walnut and tolerant varieties, your cherry should be fine. Many cherries can take up to 2-4 years to produce fruit. Also if your tree is in full bloom and then you get a bought of cold weather, your blooms can be damaged, drop off or not produce fruit. Also many cherry trees need a pollinizer. Is your cherry self-fruitful? Hope this information helps!

Robyn Says:
Dec 11th, 2015 at 5:22 am

Will figs grow under black walnut trees? I have a huge 140 year old black walnut and just planted a fig tree 10 feet from the drip line. Thank you

Suzanne at Peaceful Valley Says:
Dec 14th, 2015 at 10:22 am

I have not found much information on figs and black walnut. I did find a post about how fig production has declined in an orchard near black walnuts but no information on my educational sites.

Barbara Says:
Jan 11th, 2016 at 7:05 am

Would rainwater collected from roof surrounded by black walnut trees contain enough juglone from leaves and debris in gutters and raining through foliage to affect house plants (African violets) watered with the rainwater?

Suzanne at Peaceful Valley Says:
Jan 11th, 2016 at 11:14 am

Robyn, the juglone concentration is much lower in leaves and you might be ok to use the water from the runoff. But if you want to be safe then do not use the rainwater on sensitive plants.

Katherine Says:
Mar 17th, 2016 at 6:39 am

Would a greenhouse about 15 or so feet away from a black walnut tree be safe?  There are azaleas and other things about the same proximity away and from what I can tell they are doing okay (we bought this land about 6 months ago and things are just not starting to bloom).  The one spot I wanted my greenhouse is of course plenty close to the walnut tree, but I don’t want to waste time and money if things won’t grow.

Suzanne at Peaceful Valley Says:
Mar 21st, 2016 at 5:05 pm

Katherine: according to the University of Wisconsin, sensitive plants should be located up to 50’-80’ from the trunk.

Jessica Says:
Apr 7th, 2016 at 6:20 am

Would it be fine to mulch with woodchips that contain some black walnut parts around my juglone tolerant plants?

Suzanne at Peaceful Valley Says:
Apr 7th, 2016 at 10:25 am

Jessica, I think using the wood chips would (ha, ha) fine. Black walnut trees load their roots, buds, and nut hulls with the juglone, not in the wood itself.

gene rogers Says:
Apr 11th, 2016 at 9:43 am

can i plant a banana tree near walnut trees?

Suzanne at Peaceful Valley Says:
Apr 11th, 2016 at 10:08 am

Gene, I have not found any information on the tolerance of the banana tree to juglone. You might check with your local nursery (or the source of your banana tree) to find out about sensitivity to juglone.

Betty Says:
Apr 12th, 2016 at 5:13 am

Are red raspberries sensitive to black walnut

Suzanne at Peaceful Valley Says:
Apr 13th, 2016 at 11:03 am

Betty, if you look at the articles linked to our blog, it lists the plants that are sensitive, and red raspberries are sensitive to juglone, but not black raspberries.

Ash Says:
Apr 22nd, 2016 at 2:54 pm

I just wanted to add to the info here regarding tolerance of certain plants. We have a massive, healthy black walnut in our backyard, easily over 100 years old, and the canopy nearly stretches the entire breadth of the yard.
We have a mature fig flourishing ~15 ft from the trunk, and it puts out a big breba crop in the spring as well as a very high yielding true crop in the autumn. We also have a healthy dawn viburnum only a couple feet from the trunk, a very large english laurel close by along with a western red cedar, a norwegian maple, and a silver fir (all mature). My experience tells me all these should do well for others under black walnut as our soil is clay and not the most well draining. We also aren’t very vigilant about picking up all the fruits when they drop in the autumn.

Beth Says:
Apr 24th, 2016 at 6:10 am

Hi, I have tried many plants under my black walnut, some of the ones on the list have survived but not thrived. Specifically bee balm and ferns. Is there a particular fertilizer that you would recommend to give them a little help? I am hoping for thriving beds at last:)

Suzanne at Peaceful Valley Says:
Apr 25th, 2016 at 9:42 am

Beth, if the plants are only surviving under your black walnut but not thriving may not be due to a deficiency in nutrients but rather from the effects of the juglone from the black walnut. Don’t think that giving them fertilizer will help. You may consider relocating or put them in a pot where they will not come into contact with the juglone.

Kelly Says:
Apr 25th, 2016 at 7:26 pm

I’m creating raised beds for flowers not far from some black walnut trees - am I correct in assuming that even though I will be bringing in a 2 feet depth of garden mix soil that the juglone will affect the plants by dripping onto the beds through rain droplets?  The bed are close enough for this to happen.

Suzanne at Peaceful Valley Says:
Apr 28th, 2016 at 10:11 am

Kelly, Black walnut trees load their roots, buds, and nut hulls with the juglone toxin (leaves and stems have smaller amounts of juglone). The toxin seeps into the soil and susceptible companion plants will turn yellow, wilt, and sometimes die. So if these will be falling into your flower beds, as they decompose they will release the juglone into the soil and thus to your flowers.

Reply to this post

Your Name (required) Email, won't be published (required)

Comment

Please enter the word you see in the image below:



Find Solutions Books Fertilizers Garden Tools Growing Supplies Homestead Irrigation Seasonal Items Seeds Weed and Pest Control Other