Other than a dislike of wet soils, my experience is that this plant will tolerate and even thrive in a pretty wide range of growing conditions. Sometimes to the point of expanding exponentially by rhizomes.

There is one down the street from me, directly across from the beach growing in an untended patch of land next to the road. It gets full, all day sun and only rainwater, meaning NO water to speak of for 2-3 months every summer. Although the clump is restricted in its expansion by the road, it has grown fuller and denser over the years and there must have been 20 or more flower stalks this season. Maybe it is just a different climate but success with this plant here is almost a given!

Are you sure this is hardy enough for you, rouge? Usually rated only to USDA zone 7.

Are you sure this is hardy enough for you, rouge?

Hey 'gg', as I mentioned in my original post, I have always had the suspicion that BB might not be hardy for me. But maybe I can find a sheltered spot for it.

(Anyone in a z5/6 have an established AM?)

(I would have loved to have seen a picture of the specimen that you are describing as it sounds impressive).

I have to go that way tomorrow so will try to remember to stop and take a couple of pics. Past its prime at the moment though.

I can’t get rid if mine. It came as a tiny piece of root that sneaked in with a transplant and however much I dig out it always reappears. Perfectly happy on my poor urban clay soil. I’d be careful what you wish for.

Mine is in part shade & clay soil in a rather dry location in the root zone of a neighbor's large silver maple. It's been in the ground for five or six years and has not grown appreciably bigger. It won't grow but it won't die either. I saw a beautiful patch of BB in bloom at Filoli but mine in no way resembles that ideal.

I’d be careful what you wish for.

Not a chance that it will overstay its welcome. I am pretty sure I can count on one hand the # of times seeing a Bear's Breeches in my neck of the woods....probably more rare than seeing that other BB i.e. Butterfly Bush ;).

(I was dopey to make this purchase).

Plant Delights has some other varieties listed as 6a, so how different can your variety be, esp. as you say in a protected location. Good luck! https://www.plantdelights.com/collections/acanthus

Yup. I bought it. I'll plant it.

Correct 'gg'.

I did not know that, interesting ! I only chimed in because I've always liked that plant. Again, good luck rouge !

I love acanthus mollis and had one for a few years out in the garden, but I didn't cover it a year or two and it dwindled and I finally dug it up (in warmer zones where they thrive, it can be super hard to eradicate). It never bloomed - I think it's just too cold here.

I now grow a. spinosus and a. hungaricus - both in sunken pots and they bloom well. I just put them in pots this year so hopefully that won't change. The foliage, imo, just isn't as nice as a. mollis.

I did found another a. mollis a few years ago, and put it in a more sheltered location. It's come back even when I didn't cover it last year, but still no blooms. I think it would do better in more sun though.

You might do fine with it, rouge, if you cover it over the winter with mulch or something similar. I think I'm technically zone 6 now.

Here are the photos of the feral acanthus. Like I said, it is well past its prime for the season. Since I just drive by, I never get a close look so didn't realize it is virtually devoid of any foliage after a dry summer although there are signs of new green growth.

Excellent pics 'gg' :).

I have one- it never does anything but it is still living.

I check every so often to see if the leaves are still there but I have never seen a bloom. This is it's third season here.

I'm sure it's too dry but everywhere in my yard IS but vigilant watering manages to keep the astilbe and hibiscus going, so I dunno.

cecily 7a "Mine is in part shade & clay soil in a rather dry location in the root zone of a neighbor's large silver maple. It's been in the ground for five or six years and has not grown appreciably bigger. It won't grow but it won't die either."

Exactly.

I doubt it’s too dry. Look where gg’s example is growing. These things grow on dry rocky ground all over Greece.

So it just hates me? Kidding! Cearbhaill is a better gardener than I, my astilbe didn't last a year.

Every scrap of this one was pulled out two weeks ago. Just can’t kill this thing.

Hey @floral_uk z.8/9 SW UK did yours flower each season?

It used to but I’m trying to eradicate it so it doesn’t get a chance any more. I pull out every bit that shows. I can’t dig it out because it’s in a bed full other stuff.

It looks like Rouge and floral are probably showing a much sold type called Latifolius Group with more important leaves, less inclination to flower throughout the clump than typical Acanthus mollis.

Yes, mine is also invincible. Worse, mine is brutalissima stabiosa - vicious, prickly nightmare. Exactly the same as floral - I think I have poked my hori-hori in every centimetre of soil but seemingly, the tiniest shred of left-behind root is enough for life to spring eternal.

UPDATE (June 2023):

Absolutely no sign of this plant, this season. It 'vanished' :(.

A horrible weed. Will not die, seeds everywhere, detest it...and it always comes up in the middle of a rose or a salvia or something where I can't just heave the horrid things out. Worse, I have 2 of them - a.mollis and a.spinossissima which is stabby as well as apparently immortal. Growing in the leanest, meanest dryest spoil possible and still it thrives.

If you are determined to grow these for the foliage, get one such as Hollard's Gold which won't, at least, seed everywhere.

rouge - sorry your a mollis disappeared. Don't be surprised if you see a small plant emerge later - they really do grow from the tiniest bit of living root.

Will not die,

Except in our location.

And it was even planted close to the foundation of our home and yet it still bit the dust.

Clearly, you didn't treat yours with the right sort of life-threatening savagery to prod it into overdrive, Rouge.

they really do grow from the tiniest bit of living root.

Ding, ding, ding @ruth_mi!

I noticed this today:

The damn thing is unkillable. I now have another one popping up away from the original menace. I dig and pull every piece I see. To no effect.

I don't want to cause mental or physical distress to esteemed members @floral_uk z.8/9 SW UK or @rosaprimula :) but that scrap of plant that finally showed itself in the first week of June looks like this today:

It will be "off with its head" sometime later this summer.

Oh my goodness. You have Yellow corydalis and ground elder too!

Now 'floral', your response is exactly why I had second thoughts about showing you the plant with snippets showing of corydalis lutea and goutweed :). (I should have zoomed in on only the acnathus!)

But you kind of know me ;) and I want you to have faith in me like I think @rosaprimula has. that I have it *all* under control :).

Um nope, don't think I mentioned 'having it all under control' .What sort of gardener would you be if that was the case? Not one I would recognise....but I do hold to my original statement that the plants you do grow always look stupendously healthy and happy.

plants you do grow always look stupendously healthy and happy.

which in this case includes goutweed, corydalis lutea and acanthus mollis :)

C$$p, I had forgotten about this as today I went down that part of the garden that I don't often visit. (Don't worry, I will deal with it shortly.)

O, the joy of having 'part of the garden that I don't often visit. No chance of this at home, even with enormous plants and 'structures' (ahem). All totally visible, all the time. The allotment, however, is enormously long and quite thin and there are LOADS of parts I don't often visit. Sometimes for months (years).

'rosa' our garden, as member @woodyoak zone 5 southern Ont., Canada and @gdinieontarioz5 can attest to is quite...compact. The location for this Mollis is along a very narrow strip, right next to the foundation of the house and close to the neighbour's home where I plunk plants that I have no other place to plant. (I would never show that area to anyone who was over to visit.)

That is gorgeous, Rouge! I had always supposed that A. mollis was not hardy here, and certainly not where you live. I have had A. hungaricus for many years, it blooms faithfully and I have gotten rid of many seedlings already, but I have passed over mollis when I saw it a few times. Next time I see one, it comes home with me!

I have had A. hungaricus for many years, it blooms faithfully

A relative who lives not far from you @gdinieontarioz5 was quite proud of her "hungaricus" as it bloomed very nicely for her this season. It really gives a cool stalk of flowers eh?

Hmmm I’ve never wanted an A. mollis - fortunately! Rouge - your garden might be more ’compact’ than ours, but I think you have a larger selection of plants :-)

Rouge, I like the flowers of hungaricus in front of my Rosa glauca. I don’t have a decent photo, but this gives an idea.

Both have to spread and grow a bit yet, there is a seedling growing up to the left of the blooming plant. In a few years' time I hope that both will have filled in their spaces.

Canadian hardiness zones are based USDA hardiness(minimum temp) just with rainfall and number of frost free days included so the difference is minimal, half a zone generally.

http://planthardiness.gc.ca/?m=17&lang=en

For maps via both systems.