Hi everyone. l touched on this subject in my hello post and thought l'd expand a bit on it here. l got together a list of the clematises that l bought last year that did and did not survive the juglone poisoning given off by the Black Walnut trees in my yard. Here it is, and while not a big list, perhaps others can expand on it and those of us who have those beautiful, but toxic trees can learn which clematises not to plant within its 50' permiteter. I've included their pruning groups to see if there might be a pattern - I'm seeing that group 3 seems to be less tolerant, but that's only from a list of 4, so l look forward to other people's experience.

Clematises that did not survive:

C.'Helios' (group 3)
C. 'Dutchess of Albany'(group 3)
C. 'Nelly Moser' (Group 2)
C. 'Huldine' (group 3)

Clematises that did survive:

C. 'Allanah' (group 2)
C. unknown large white-flowered
C. 'Tage Lundel' (group 1) (thought this one hadn't, but when I just went out to get its name I saw new growth!)
C. Multi-Blue (group 2) This is the first one that I planted shortly after we moved in, and is about 40 feet away from the closest BW.

A bit of an update; spring is springing all over my garden and two clematises that I previously thought were toasted, have new growth!

C.'Helios' (group 3) is a clemmie that I initially had planted at the base of the closest Black Walnut to the house. I moved it in the late summer to the other side of the yard, and it just slowly died back and so I erroneously thought it had succumbed. Wrong!! New growth spotted this aftrnoon.

The next is C. 'Huldine' (group 3), which is planted about 20 feet from the same BW tree along the fence. It grew a okay last year but didn't flower, and died back fairly early in the fall. I spotted that telltale clematis-like new growth pushing up out of the ground this afternoon.

C. 'Allanah' (group 2) - ah, this one I'd listed as having made it because it grew really well last year, although didn't flower and was one of the last in the garden to die back. I'm seeing no new growth whatsoever on this one. It's planted about 10 feet from the BW tree, but up a little hill. I'm not giving up on this one yet, because its flowers are supposed to be really awesome-6-8" wide; perhaps its just a late starter. In my old house I had a sweet autumn clematis planted on the north side of the house, and it wouldn't push up out of the ground until the 1st week of June.

So, perhaps I'm down to two true clematis deaths due directly to BW trees - C. Nelly Moser and C. Dutchess of Albany.

Perhaps if I had left C. Helios planted at the base of the BW tree, it would have died; I'd like to think I saved it by moving it. It sure did zero growth-wise when it was planted there, it was very vigorous and lush when I got it, and it just lost vine after vine.

Time to start dinner. If anyone else want to share their experience with these trees, please feel free to chime in!!

Hi. No updates on my own, except the ones that survived are all growing nicely. I however found out about a few more clematises that have grown well despite the juglone poison. They are: C. 'Dawn', C. 'Texensis', C. 'Mrs. Cholmondely' and C. 'Markham's Pink'. They're on my must have list!!

I had Duchess of Albany, Fireworks, Jackmanii Superba and Jackmanii all under the black walnut trees. They did fine except there wasn't enough sun, so the clematis didn't bloom much.

One thing to keep in mind when planting anything under a black walnut tree is that the fully leafed out canopy sheds water. We can get heavy rains, the rest of the garden will be well watered, and many times I still have to water the hosta under the BW trees. Black walnut trees are also very heavy feeders. The feeder roots seek out moisture and nutrients, so if your clematis is near a root, the tree is probably taking the nutrients.

Thank you Julia; that's really good information. Perhaps it was something else that killed my Dutchess then, since it was planted about 15-20 feet away from the BW, and on a raised portion of my backyard.

I'm seeing lots of new growth now from all of them - perhaps most from the 'Tage Lundel' which is just going crazy on its host, the so far leafless Rose of Sharon.

What zone are you in? Parts of Ontario are very cold.

Are you sure it died or is it waiting to make an appearance?

I'm in south central Ontario, on the north shore of Lake Ontario, zone 5b I believe. This was a particularly bad winter in that we didn't have much snow; snow will protect the plants more when it gets really cold. Empress was dead last summer; I moved the whole plant across the yard with its drying up vine hoping it was just dying back early. I'm an eternal optimist. I keep watching the place where I planted it and nothing's happening. But I'll keep watching, because I've seen new growth from a clematis as late as June 1st.

Just like C Allanah - I took its obelisk away but haven't disturbed the area much yet. Even though I have another red flowered clemmie ready to plant in its place - C Rouge Cardinal.

Its too cold here yet to put new plants into the ground - there's a frost warning for tonight. We're okay after about the 12th of May, so I'll plant all my new clemmies next weekend - yesterday I went hunting for clematises that others have found will grow, and the only ones I could find were Rouge Cardinal and Mrs. Cholmondely. So I bought them and two others - one for a patio planter, C. Cherokee, and a 'nodding' white clemmie for the front yard, C. Gazelle, to compliment one I bought last week, C. Purpurea Plena Elegans - I'm going to plant them at the base of my flowering crab. Gosh, I hope that won't open a new kettle of worms!

Not sure where to put Mrs. Ch. yet; will have to go out and commune with nature for awhile; it'll come to me sooner or later.

Lack of snow is a problem. We had years like that and I always seemed to lose 5-6 plants. The last few years have been different thought. Our first snow storm last year was 14", which lasted until March. It makes a big difference.

I was curious about people's successes with clems near black walnut trees, thanks for posting.

I was afraid to put any clems in my northern back yard bordered by black walnut trees. I had read that Clematis armandii was immune to juglone on several websites, but was afraid to try.

I successfully wintersowed some clematis seeds, Clematis tangutica 'Radar Love' so I am trying several seedlings. I will also try some in my front garden, safely away from the black walnut trees.

That's great Andi, trying several seedlings in different places might be the key to finding out just how far you have to be from the trunk of the tree for that type of clem.

My husband has kept saying that we need another clematis with an obelisk on the other side of the patio to balance it out, but its were Dutchess of Albany was planted last year, and died. So, I yesterday planted Mrs. Cholmondeley in that spot and will keep my fingers crossed.

I hope it does well for you. I am planning on mine climbing a honeysuckle.

Honeysuckle is supposed to be resistant to BWs so I'd be very interested to find out if that's true.

Mine is resistant. I have the main plant in a pot, but it has grown thru the bottom. A couple of stray cuttings have rooted and are growing well. My plants are the plain , white honeysuckle, but I want to try some of the coral types next. I added three lavender rose of sharon seedlings in front of the honeysuckle. They are listed on "immune" lists, I'll see how they do.

I also grow hostas, orange ditch daylilies, tiger lilies, pachysandra, sweet woodruff, wild violets and wild strawberries. I want to try some zinnia and calendula this year. The seeds are starting in a pot at the moment. I wintersowed black hollyhocks and planted the seedlings. Unfortunately, the weeds aren't immune to juglone, especially that white creeping stuff. I had to cover the ground around the hostas with newspaper, then I didn't like the look so I covered the newspaper with brown paper bags.

Trumpet vine climbs the trees. If you want a vigorous, flowering vine and don't mind keeping it in check it thrives on black walnut trees and hummingbirds like it. (The trees and trumpet vine were here before I was).

I killed a lot of plants until I learned about black walnut trees and juglone. Now, I call that part of the garden the tiger garden -all hostas and orange and black plants.

The woman who owned the house before us lived here 50 years and figured out what to plant and what not to plant and where. So there's lots of hosta, lots of euonnymous, bell flowers galore, phlox everywhere and there were lots of non-blooming iris that we took out. There are also several lilacs, more than 50 feet away from either tree and a few flowering trees including a Rose of Sharon. The backyard garden is famous for eating perennials and vegetable plants. I planted a bleeding heart beside one of the trees last summer. It came back this spring but, while still very pretty, its painfully tiny, I'm a little embarrassed by it...lol... I guess its a fighter or it wouldn't have come back, so I'd better move it, maybe to the front yard.

I have a struggling rhododendron. I got it from a friend who was moving. Put it in the back, knowing it liked shade, not knowing about juglone, yet. It did alright the first year. The next spring, it was nearly dead. Then they cut back some of the trees, it died more Then I read about juglone and black walnuts. I brought it to the back of the front, south facing garden. Even shaded by other plants, the leaves burned. It is now in the back in a pot. I make sure no leaves fall in the pot. Of course, it is not directly on the ground. It is smaller than when it started, but recovering.

The hostas are doing great. They were also from a friend...They are huge this year! I divided the one big group last year and now have three huge clumps. I think they are sum and substance. I would love to grow grass on a walkway against the fence. Tried three times. It germinated, but never thrived. Maybe I need to loosen the soil? What a chore. Any suggestions for a walkable juglone and shade tolerant ground cover that doesn't need mowing? One neighbor has weeds the other gravel....would prefer something more....attractive.

I killed a bleeding heart, but have an alba bleeding heart growing in the front yard. I am trying to shade it with other plants. I even killed rhubarb. I'm looking up euconomis. I also read that mayapples are juglone tolerant, have to learn more about them. I have zinnia and calendula seedlings that I will relocate when they get a bit bigger. They are juglone tolerant, but may not get enough sun. I am able to grow lettuce. I grow my salad lettuce in windowboxes, but I always plant a bit near the fence for the bunnies and groundhog, hoping that they leave my veggies alone. I have my front garden full of flowers, so I grow veggies in containers.

In addition to the black walnut trees, the back area has a tall wooden fence and compacted, poorly draining rocky soil. My "neighbor" on the other side of the fence is a graveyard with plenty of graves circa late 1800s to present. I am clearly the first person to try to garden here. I started amending the soil with kitchen scraps and earthworms and took it from there.