Jan, I think we may be of a very similar mind on this! Though perhaps my feelings are a bit stronger on it! IMO, there is really very little "zone-pushing" done - I've come around to thinking that the few things I'd put in this category are truly tender perennials and woodies that NEED protection and coddling to get through winter.

I think what we are doing is just proving that various species are actually zone 3 hardy, when the "literature" (by which I mean the accepted info, however misleading, that we see in books, websites, plant tags, etc.) would make the otherwise untested claim that the same plant is zone 5 or 6 or whatever. Another thing is that less experienced gardeners, when they try plants that are new to them, tend to think of it as "zone-pushing" - it's terrifically interesting to try new plants, but it's not necessarily zone-pushing - but call it whatever makes you happy, LOL!

A case in point - Lysimachia ephemerum - the literature would claim it's tender (zone 7-9 in one of my sources), however I see that it's now offered by Gardens North and rated as zone 4. Obviously, people in colder zones are trying it and finding it hardy. So, the assumption of it's range being "zone 7-9" was, IMO, an untested assumption and clearly incorrect.

Anyway, just a note for now....interesting subject, more to follow.
Lori

Do you think the internet has attributed to this - rather than having to rely on a book written by someone in a warmer zone, or the few seed catalogues of a few years ago claiming what grows in which zone, now there is such an abundance of information, on-line sources, exchange of knowledge. I'm certain that if I didn't have internet access (and living where I am living in sticksville) I'd still be stuck looking at incorrect or outdated information believing it to be true. I probably would not know about Gardens North. I would not have attempted growing ornamental grasses, much less giving plants like Miscanthus, Panicum or Calamagrostis a whirl. Really, I think I would be bored.

Jan makes an excellent point about soil/moisture, etc. And perhaps often when something dies and we try it again we unfortunately try it in the same spot in the garden, same conditions, same death. I also think that planting for your soil conditions is important. I won't bother trying plants that prefer soil on the acidic side since mine is quite alkaline, and when I incorporate plants that like alkaline soil, they thrive with so little care it's childsplay. This is trickiest with shrubs since their root structure is so much deeper than a perennials. You can amend for perennials to some degree, but it's way more difficult for a shrub. I also think zone ratings for shrubs are more accurate than those of perennials - there's been more testing and published results.

I agree totally on that point too! The right conditions, so to speak, promote "hardiness". The wrong conditions, falsely, suggest lack of hardiness.
I think the value of the internet in this case is the opportunity to read peoples' actual personal experiences re. growing plants.
By contrast, I find a lot of the commercial sites just repeat the same old incorrect zone ratings, that have been copied from book to book to book, and now, to the internet...with the aforementioned exceptions, of course, of places like Gardens North, Bluestem Nursery, Rundlewood Gardens, etc.. More and more of them, yahoo!
Lori

Agree, Lori and Pudge.

A few more comments....if you can stand it! LOL.

I find when I research plants, that I do use the Canadian sites mentioned by Pudge. The Canadian nurseries tend do a much better job of zone ratings....probably because they serve a far north clientle and some are actually located in cold zones. On this side.....the vast majority of the population and nurseries are in the warm zones . There seems to be a tendency to give the plant a rating of whatever zone the nursery is located. Ergo....lots of Zone 5 and warmer.

I also look to the plants native habitat although that is not always a good indicator since there are quite a few exceptions. But...sometime it is a starting point. Just love when something is listed as native to Russia, Siberia, etc and then given a zone 5 or 6 rating. Just what the heck were the complaints about being exiled to Siberia if it is like southern Michigan? LOL

I find most reference books to be the most pathetic when it comes to zone ratings. My newest editions of the AHS A-Z Encyclopedia and Allan Armitage's book are huge disappointments on this issue. Yes, thank goodness for the internet and a chance to know of actual experiences with plants.

As an aside and to give an example of the 'right conditions'.....my recent interest in Bush-type clematis is because a local gardening friend told me bush Clematis do very, very poorly and barely survive. So....sounded like I needed to prove her wrong! LOL. She is a great gardener with a vast number of perennials....but she gardens on heavy, heavy, wet clay. We don't even come close to having the same experience in survival or performance of perennials....you would think we lived many zones apart rather than 15 miles.

Another 'thank goodness' for this Forum. Over the years, many of the new perennial species I have added to my garden have come from the experience of folks on this forum. Just where would I be without all the great ideas I glean from here?

Anybody growing Sanicula caerulescens? Can I put it in the 'Tried and True' or do I have to find out for myself?
Jan

Lets see.
I have had one Iris pallida "Argentia Variegata" out of two I planted last year come back. These came from the local nursery.
I also had one Iris tectorum seedling survive. That was out of three seedlings.
With all these irises they looked good in early spring but the ones that expired did so in the spring with temperatures cycling around freezing.
I generally wonÂt try established plants unless I know that they are hardy here.
OTH I will try seed as the cost of failure is limited.
Ian

Those are cute terms, "Noah's Ark" and "zoo". I suppose it could be sort of a botanical zoo. I jokingly tell friends my yard is my own private botanical garden. It's quite small and alot smaller than most botanical gardens, but my mission is to cram it full of as many plants as I can, tastefully done of course.

A very interesting discussion. There's just so many variables involved in a plants survival, it's definitely not an exact science. In my mind, one might also divide zone pushing into two categories: plants that survive winter via natural means (snowcover) and plants that survive winter by "artificial" means (the use of mulches, protective covers, etc.)

My zone 5 Japanese Maple survives winter after I mulch it heavily and basically bury it. I could say it survived a zone 3 winter, but I guess the tree itself wasn't really exposed to the elements of a zone 3 winter. It's not like I planted it in a bare field in zone 3 and it survived. Still, that's one thing I like about zone pushing, thinking of interesting ways to help a plant survive. It's like an extreme sport or something (extreme gardening?)

The second thing I like is that zone pushing allows a person to grow a plant not very common for their area. A person in zone 5 might be bored with boxwood, but I look at mine and think "Ah, how cute, look it not only survived winter, it grew 6 inches". But, in order to go through the trouble of zone pushing, and especially winter protection, a plant has to be special. Of course everyone's list of what plants might be special would vary.

I agree that price is a factor in determining what to experiment with. That is why I like obtaining seeds or else cheaper smaller plants. Sometimes stores like walmart get some "out of zone" plants in with their shipment. I bought Hick's yew one spring for $5 so decided it was worth a gamble. Haven't seen it there since. Last year I bought a blue boy holly from Home Depot for $4.

The internet is a great spot to not only obtain seeds, but also to do research about a plant that you are about to try growing. I try to go to many sites to at least get a feel for the conditions the plant likes and the average zone rating.

I had iris palida survive as well, though it was in a very sheltered spot with great snowcover. Vinca minor "illumination" survived as well, which surprised me because I literally just dug a hole and plucked them in the ground in late September.

Sometimes plants are hardier than the zone rating indicates but sometimes they are less hardy. I mail ordered star showers virginia creeper (parthenocissus quinquefolia) and it has suffered dieback every year. It finally has a decent root system to be able to grow about 5 feet high in one summer, before winter killing to near the ground. The garden catalogue I bought it from said zone 3. I recently saw the plant offered again this year and they have changed the zone rating to zone 5, which is probably more accurate.

My pet peeve is seeing acer negundo 'flamingo' offered at a couple of big box stores listed as hardy to zone 2. The species acer negundo is hardy to zone 2, but the 'flamingo' cultivar is considerably less hardy, probably to zone 5. I just feel bad for unsuspecting customers who might read the tag, shell out 40 bucks, only to have a tree that either dies or performs badly. Sometimes though, out of zone plants can be used to one's advantage. If acer negundo flamingo did survive but was more like a small shrub than a tree, well, one might be able to fit that into their yard somewhere and use it to their advantage.

But, St. John's wort was the one plant that didn't survive winter here. Maybe it was it's location which stayed wet and soggy that fall.

Glen

Several more excellent points, Glen, and I'll pick on one in particular - that out of zone plants may stay smaller which isn't always a bad thing. I've situated a Purpleleaf Sandcherry where I want it to be a small shrub - if it didn't suffer tip kill or if it grew by leaps and bounds I'd have to be constantly pruning or move it. There is, though, a difference between hardy and surviving, and hardy and thriving. Again, not so evident with perennials perhaps, but definitely for shrubs and trees. I have had a Weigela for several years but it dies almost to the ground every year, even with lots of snow cover. This shrub blooms on old wood hence I've only had it bloom once or twice, way down near the soil. Aside from the blooms, this is a pretty ho-hum plant that probably isn't worth keeping and the space better served by something else. But it is surviving a zone 2B winter for going on 8 years.

Anyone else growing Acanthus hungaricus?

I have 3 now, including a self-seeded seedling I just discovered last week. I plan on moving it to my unprotected, cold front yard next year.

Put on quite a show when flowering.

I hate mulching tender perennials (more work), will only mulch one this winter, hopefully all will survive.

Jan, you're on your own with the Sanicula caerulescens - unless someone pipes up shortly! Heck, I had to look it up! Does look very nice..."extremely long bloom season" was mentioned...appears to be offered by Terra Nova.

Glen, I have long lusted after Acanthus, so it's great to hear of your success with a species of it! Please do let us know how it does without protection (since that's where I draw the line, LOL!)

The_Passionate_Thumb,
Gee, that sounds so formal...may I just call you "Thumb"? LOL! My Cyclamen purpurascens are in:
1) deep compost under a columnar pine (so almost full sun), and;
2) unimproved clay, alleviated only by a top dressing of bark mulch and decayed leaves, in mostly shade under an ornamental crab apple. Actually the latter seems to be growing more quickly. From this limited experiment, I'd say they're pretty adapable - many people also grow them here as rock garden/trough plants, so evidence of further adaptability.

Okay, here's one I've tried many times and have never been able to winter - Alchemilla ellenbeckii. Anyone succeeding with it? (The other alchemillas I've tried - mollis, alpina, erythropoda, and now, faroensis - seem indestructible.)

Really? Is Alchemilla alpina easy to grow, too? I've read that Alchemilla saxatilis was supposed to be "easier to grow" than Alchemilla alpina, which left me wondering just how difficult the latter really was. I like the little shiny, dark green leaves. I think they are charming.

Does anyone grow Geranium 'Rozanne', Aster 'Monch', Beautyberries, or Rosa 'Jeanne La Joie' in cold climates without protection? I know the latter will grow in Colorado zone 4 (thought it's rated zone 5) without protection.

Sharon

Sharon, haven't had any problem with Alchemilla alpina here in regular, alkaline, improved clay soil in full sun - although I expect its form is much different than if it was grown as an "alpine".

Alchimella alpina is easy to grow. Every bit as easy as A.mollis and A. erythropoda. Have all three in good rich soil in full sun.....only because I have so little shade. The alpina gets a bit of shade this time of year. The charm of A. alpina is that very thin silvery edge. I don't grow the other two mentioned by Lori....at least not yet!

Acanthus hungaricus! Am impressed you are growing it, Glen. AHS rates it zone 6. Armitage says zone 7. Hodgson grows it in zone 3 with heavy snow cover and says it is "popular in zone 3 gardens". Also, says the main problem is not the actual winter hardiness but that it emerges fairly early and late frosts can kill the top and it won't bloom. Recommends mulching to assure blooming. But sounds like that has not been a problem for you since it has reseeded.

Geranium 'Rozanne'....absolutely the best but based on what folks say on other forums it is not hardy in Zone 4. Even iffy in zone 5? Last year I dug mine and stored it in the potato cellar. It is the only plant I fuss with. Like Lori and some others, I don't fuss or mulch or do anything to assure winter survival. 'Rozanne' is the only exception. I'm thinking it might be one of those plants that blooms itself to death...like some of the fancy Gaillardia cultivars. So...this year I am going to try cutting it down (any day now) in hopes in won't go into late October in a full, roaring bloom with no preparation/settling-in for winter. Will see if that works although I hold out little hope it will.

Jan (busy adding to her 'To Get List'.)

Jan - I've had one A. hungaricus for years, has been flowering since 2001. Divided it last year, no flowers last year, but great again this year.

Sounds like to be safe on flowering I may need to continue to mulch them, boo.

Great picture, Glen. Looks like a winner. I am rather chagrined that I didn't remember this plant being on your site. I go their fairly often since I use it as one of my references....but somehow I missed or didn't remember the Acanthus.

It will be interesting to see what happens to the blooming on those you don't mulch. Suppose it might vary from year to year, depending on the occurence of a cold snap/hard freeze after emergence.

As you probably know, most sources issue dire warnings about the massive root system and invasiveness of A.hungaricus. Ahhh....yet another problem cold-zoners don't have to deal with. LOL.
Jan

Jan - invasiveness I hadn't heard of, nor experienced. Do you have any more info e.g. underground shoots?

Well I'm pretty sure I'm out of my league or zone trying to grow Perovskia Russian Sage in 1b. I noticed Glenn from Sask rates it as zone 5. I think I started the seeds in 2003. The plants survive okay, but only come up from the roots and take very long to do that although spring in both 2004 and this year was unusually cold. Because they've taken so long to shows signs of life, I've accidently dug up several. I now have one starting to bloom in the garden, so I guess I'll have to wait another year to decide if there's a chance in it doing better. Marie

I agree with those of you who suspect zone ratings are often wrong just because the plants haven't been tested in colder climates, and I can understand that. But I don't understand what must be lack of research (and I mean just looking something up, not scientific research) in other instances. For instance, usually Mimulus guttatus is listed zone 5 or warmer, but it is native to the area of Alaska I live in.

Mytime - totally agree about the lack of basic knowledge on the part of the so-called experts. Just drives me nuts when I see cold zone native plants rated as warm zone only. Sheesh! Any half-way decent wildflower book gives the native range. Apparently authors don't own a wildflower book!

Glen - invasiveness of the Acanthus in my references refers to the underground root vigor. Here are some direct quotes.

'Herbaceous Perennial Plants' 2nd edition, by Allan M. Armitage. Armitage has a PHd in horticulture and is a research horticulturist. He rates A. hungaricus as zone 7-9.
"Once established, Acanthus is almost idestructible and will colonize and area with its invasive roots. If one tires of bear's breeches and wishes to remove the same, it is next to impossible not to leave some root pieces behind, which, like amoebae, will regenerate and recolonize their old hoemsite."
"...most authors state that it [Acanthus] is insufficiently hardy for the north. Those authors need to see the wonderful plantings in Gardenview Hortifultural Park, located in Stronsville OH, zone 6. Persistent, long lived and certainly cold hardy"

Apparently Armitage thinks Zone 6 is 'the north'. What a hoot!

'Perennials for every purpose' Larry Hodgson
"For bear's breeches to be truly low-care, you have to plant them inside a root barrier such as a bottomless bucket sunk into the soil. Otherwise they can be aggressive, sending up new sprouts from their long underground shoots."
"Although it [ A. hungaricus] is the least known of the bear's breeches, this species adapts to a much wider climatic range than any of the others. It also blooms later, so it is more likely to flower every year. ....it is quite popular in USDA zone 3."

I should note, AHS, Sunset and DiSabato make no mention of invasiveness and describe Acanthus species as clump forming.

I think this proves the point that you cannot believe everything you read! Or maybe...who do you believe? Reinforces the points made in earlier posts on this thread, nothing beats the actual experience of growers in the cold zones.
Jan

Are the leaves of a mature Alchemilla alpina plant still only about 1" across, or do they get bigger once they're in the ground?

Does anyone grow Aster 'Monch', Beautyberries, or Rosa 'Jeanne La Joie' in cold climates without protection? (I keep my Geranium 'Roxanne' in a pot and bring it inside, too.)

Sharon

Thank you Jan for the info, interesting reading. I wonder now if my 'seedling' is instead a sprout from a root from mama? Too late in the year to mess with it, I'll have to check next spring when I move this sprout (assuming it overwinters).

Mytime - Mimulus guttatus is native to Sask, too, I was looking at some patches of them a few weeks ago along a creek in heavy forest in our Cypress Hills, zone 2. I grew a bunch from old seed this spring. Lots germinated and now have some alarming patches in my garden. We had these 6 or 7 years ago in our garden, bloomed too, but my wife thought they were weeds and yanked them all one spring. Side note, one of my favourite plants in my garden is Mimulus lewisii, which I can't determine if they survive by self-seeding, or as short lived perennials, or a combo of both. Very nice reddish pink flowers.

North53 - Russian Sage only survive one or two winters (with heavy mulching) in my unprotected front yard, but are pretty reliable in my protected back yard. The problem is I want them in my front yard. Oh well, they're pretty cheap to buy here, every year I buy one or two to replace the goners.

Good for you starting them from seed. I wrote off ever trying them from seed after reading somewhere (I'm guessing Lois Hole's Perennials book) that starting them from seed is difficult and not recommended.

----

The worst rating I have ever seen for a plant was in a magazine article about Agastaches. It listed Agastache foeniculum as hardy zone 6! Whoa there, grows wild here in zone 0.

The best zone ratings of perennials for cold zone gardeners I have seen is the Heritage Perennials Perennial Gardening Guide. I think they use a lot of input from gardeners from across Canada for their ratings, has been a very reliable resource for me.

Sanicula caerulescens - Planted it last year in a very dry, part shade bed that was raised (a whole) 8 inches next to a sidewalk. Virtually no snow last year, and it died over winter, although I can't say is was actually happy anytime last season. A new plant, but it did bloom a few times. Still, in the same bed where it died, theses survived in my zone 4a: Epimediums davidii, diphyllum 'Roseum', grandiflorum, grandiflorum 'Lilafee', lishihchenii, youngianum 'Niveum', Haquetia epipactus, Aruncus aethusifolius, Digitalis 'Spanish Peaks', Iris gracilipes.

Rick

Interesting thread! Having read this I can be encouraged to go ahead and "zone push" too. OH MAN, that adds loads of new/fun things to try!

Thanks Glen for the clarification on Russian Sage hardiness. Maybe I'll try mulching to get them to come up earlier in the season. But once they're gone I don't think I'll try replacing them. It was an experiment.

I agree with your assessment of the Heritage Perennial Gardening Guide. I have an old version. I try not to go into a nursery without it. It saved me from buying Sisyrinchium striatum (Yellow-eyed grass) off the perennial clearance table at a local nursery. It was rated zone 7-9 in the book. When I pointed that out to the worker, she said 'oh we're selling it as an annual'.

I grew agastache this year (hasn't done much), but i thought it was annual. It's in a container so maybe i should put it in the ground?

Marcia - I checked one plant reference book that lists Agastache as "genus of about 30 species of aromatic perennials".

I've had A. rupestris plants overwinter, though most die. I mulch these plants quite deeply. This one is native to the US southwest, a zone 5 rating is the most generous I've seen for it. I highly recommend it even as an annual - flowers well it's first year from seed. Very showy (big) if you can overwinter it. Flowers pink/orange.

There are a number of Agastache hybrids and species that are rated zone 6, essentially an annual for most of us.

A. foeniculum is definitely hardy. The Perennial Gardening Guide mentioned earlier lists variety 'Blue Fortune' as hardy z2. Anyone growing it? Other hardy species?

Sharons2, the leaves of my Alchemilla alpina stay small; it's my favourite miniature plant. The reverse of the leaves looks like it's made of silver silk. I must not have it in the best location, though; it's totally hardy, but it does not increase very quickly. I gave a small division to my sister last year, but she promptly killed it. She'll have to wait awhile before I dare give her more!

Very interesting thread. I like to try challenging plants, too, and I've learned that zone ratings are only approximations. I read, somewhere, that "official" zone ratings were originally only meant to apply to woody plants, and not herbaceous perennials at all . That makes sense to me, since trees and shrubs (unless you wrap them in burlap like mummies--and then, what's the point of trying to have a nice winter landscape?) are more exposed to the elements over winter.

Even so, some shrubs (if you don't mind them regrowing from the ground each year) will live happily a zone or two below their optimum hardiness. I bought a Cotinus 'Royal Purple' (Purple Smoke Bush--rated zone 5) about 4 years ago. Each year, I have to wait until late May or June before it shows me it's still alive and, of course, it never "smokes" because the plant does not flower on new wood, but I still love it for the shape and colour of the leaves. It gets to be the size of a large perennial, and that's just fine by me.

Jan, I thought you'd be interested in the following description of Allan Armitage. You'd think that someone growing up in Canada would know a thing or two about the colder zones. How soon they forget!

..."World-renowned horticulturist Dr. Allan Armitage...bases his descriptions on extensive personal experience he has garnered from decades of digging in the dirt. Although he currently gardens in the sweltering confines of Athens, Ga., Armitage is no stranger to the unique challenges of gardening in a temperate climate.
Raised in the cold clime of Montreal, Quebec, he did his undergraduate work in horticulture at the University of Guelph, in Canada. He then spent another couple of years digging in the test gardens of Michigan State University, while earning a Ph.D. in horticulture." (http://www.detnews.com/2001/garden/0112/05/e10-334092.htm)

Doris

My Agastache is "Blue Fortune", so i'll transplant some into the ground. Thanks, Glen - i guess i should learn to research some of these plants on my own, eh? LOL Nah, that's what this place is for!

For years my attempts to grow Russian Sage produced dismal results. The plants, in an unprotected spot, never died but cetainly never thrived. Lucky if they got to be 1 foot tall by the end of the summer. Hardly stunning!
Then...one day I was at the home of a local gardener....one of several around here that is way up in years and has lived on the same homestead for well over 50 years. She had been busy digging out much of a huge clump of Russian Sage because it was so vigorous and had way outgrown its space. Needless to say, with her permission, I rescued some from the compost heap! She did not remember where she had orginally obtained the plant...."probably from my mother?"
I have had it in my garden for about 3 years now and it is amazing! Zips through winter without a problem....grows vigorously, and blooms profusely all summer. Not even in the same ball park as the ones I had been purchasing. (all are P.atriplicifolia or variation thereof.) I think Rick would call this an adaptation of a species or an adjunct population?
Wish I could share it with some of you in zone 2. Would be interesting if it exhibited the same vigor. But...the Plant Police at the border would cuff me and beat me about the head! LOL.

Glen - I grow Agastache rupestris, foeniculum and 'Blue Fortune'. All winter here fine. Occasionally I will lose A. rupestris but like you said it reseeds very well. Armitage rates A.rupestris as Zone 5 and A.foeniculum as zone 6.
I planted A. schrophulariifolia this spring. It is almost 48" tall and blooms pink. Has yet to winter so time will tell. Seller rates it zone 4 so I think it has a good chance.
Thanks much for a book recommendation that does a decent job of zone ratings.

Rick - thanks for the info on Sanicula caerulescens and the epimediums. I have always only grown Epimedium rubrum. This year planted a couple of E.youngianum's. If they make it, I will probably go hog-wild trying them all!

Doris - Yes, I know Armitage is Canadian. It is one reason I bought his book. Thought it would be a great resource for northern gardening. He is currently with the University of Georgia (zone 7)and the focus of his book is on the warm zones. It was a real disappointment to find that his 'experience' with hardiness does not seem to go north of zone 5 or 6. To be fair...he does have some accurate zone ratings....but when he is wrong, he is really wrong! Incidentally, did you know Dr. Michael Dirr of tree and shrub fame is also at the Univ. of Georgia?

Jan

Cool. David_5311's pictures of Agastache 'Blue Fortune' always made me drool in the perennial forum, but I figured I could never grow it after looking at the zone rating. Same with the Epimediums, and Cotinus 'Royal Purple'. I'll have to pay more attention to them at the nursery now.... And Helianthemum and Bellis perennis (which I found on the Heritage Perennials website - Thanks, Glen!)

Is the Heritage Perennials Perennial Gardening Guide just like the website? With the same information and everything? I'm more comfortable with English measurements than Celsius and Metric. Does it include the number of weeks each plant blooms?

I've grown Russian Sage for the last 2 years, and it's done just fine. I also have a 'Monch' Aster which I'm wondering if I need to bring inside before winter. Has anyone tried that?

Sharon

Jan, about the Russian sage with a special cold hardiness: I guess you were thinking "disjunct population" adaptation, and that or normal genetic adaption may be true, but not quite as you think. (Or else I'm not understanding you correctly.)

Genetic adaptions occur over time and generations. How many centuries or millenia did you say that lady had the plant? Just being facetious here, but it does make the point. The likely scenario is she just happened to get a plant that was from an original wild population that had already adapted to colder temperatures. I suppose that her plant could have produce the right mutation for the observed cold resistance. But giving it the odds of one in a million would be very generous.

BTW, that Sanicula was in a new bed last year, so all the plants listed were new too, and all endured with the same time conditioning. Stay tuned as I have added Epemediums 'Saxton Purple", pubigerum, stellatum 'Wudang Star' and sutchuensis, although not all in that same bed.

Rick

Sharon - I haven't looked at their website in a few years, but I recall it being similar to the book. They have the same info per plant on their site, the book, and their plant tags. Book has plant size in metric and non metric, and book has bloom time for each plant. I have the 4th edition (time I shopped for a new one, maybe is a 5th by now), price on it is 17.95 cdn.

Rick - Yes, I do understand the 'disjunct population' thing. Believe it or not, my reading comprehension is O.K. despite typing 'adjunct'. AURGHHHH!

Actually, the reason I think some of these garden-worthy species, that have been growing for umpteen years on old homesteads, do so well is because they are 'originals', so to speak. Unlike, the named varieties available in nurseries today, these species were obtained before somebody 'messed' with them. None of this 'Little Spire, 'Filagran', 'True Blue', 'Buy Me Too'! In an attempt to make a plant shorter, more filigreed, a different blue, or whatever they just wring the hardiness right out of them.

Has anyone tried growing Darmera? Hodgson says D.peltata (aka Peltiphyllum peltatum) does fine in Zone 3.....albeit you would need a lot of space and moist ground.

Jan

Yes Jan, I tried Peltiphyllum peltatum. A goner, didn't like Regina winters.

I vaguely recall it wasn't happy even during the summer, not a good sign to attempt overwintering. Perhaps would best in a bog garden in cold zones.

Sorry about the wrong assumption, Jan. I think we are on the same page. But for the benefit of others, let me clarify a point:

Plain species are, in general, more cold hardy than selected clones. I say in general for a couple reasons:
(1) some selected clones are selected specifically for cold hardiness(Duh!)
(2) Rarely, cultivars selected for some other desireable quality just happen to be from extra cold hardy stock. An example would be Cupressus(aka Chamaecyparis, Xanthocyparis,...) nootkatensis 'Pendula'. It is more cold hardy than the species in general. (Sorry about the taxonomy there. This one is in real turmoil.)

Likewise, the vast majority of cultivars are not selected for cold hardiness, and since:
(1)the vast percentage of a gene pool usually does not have the more cold hardy gene, the clones do not either.
(2)Those cultivars carrying your local genetic provenance (non-imported) are comparatively rare. Imported cultivars tend not to be gathered from the the most northerly or highest elevation of their distribution, especially in it's first introductions, whose genetics include the majority of cultivars. In addition, they might be the only introductions of the plant. So these clones are usually not as cold hardy. The same could be said for the species in general, but the hit and miss percentage should be higher for cold hardiness.
(3)Add to that a common reason for selection - vigor, that compounds the "problem": more vigorous populations of a species are in general less cold hardy than the norm of the species. Slower growth and smaller size tend to be an adaption to colder or more harsh climates. For example, alpines.

So it would seem to follow that compact or less vigorous cultivars would tend to be more cold hardy. Yes, but only if those clones were originally selected from a wild gene pool adapted to more cold. That is not usually the case. Most of the time, dwarf mutations are discovered or bred in cultivated gardens, and not sought out in northerly and high elevation distributions of the species.

Well, ya got me going on one of my favorite subjects. Please excuse my straying from the thread subject.

Rick

Sharons2, Aster 'Monch' was highly recommended by the herbaceous perrenial trials in Calgary. It shouldn't have a problem where you live.

AbGardener, thanks for the info on cyclaman! It's definetily a plant I'm excited about.
Is PT a less formal name?

Leftwood, I found your discussion intriguing. If you omitted anything can you include it now?

Maybe we should talk about measures one could take to increase the survival rate of "marginal species".

Every plant is exposed to the environment. Properties of the environment precipitate a change in the properties of the plant. If the plant is "stimulated" enough (which can be to a smaller or larger degree) it's own properties will change enough to effect other parts of the plant. I believe that for many plants it is mostly the preparation for winter that determines whether or not it will survive.

According to this idea if the plant is "stimulated" in a similiar way to what it would be in it's natural environment things should snowball enough to give it a thick covering over winter.

If this is true one would need to know the biology of the plant to have the greatest sucess with overwintering. Some plants could need more water in the fall to overwinter whilst others might need less water to overwinter.

My mother-in-law gave me a couple of Anagallis monellii last year, and true to my form, I just plunked them in the 'holding' bed, assuming that I'd get to enjoy a few blooms for the remainder of the season and then that would be it.

What a surprise when late this spring something came up where they had been planted and right now they are blooming their little hearts out!! Gorgeous! I thought these were annuals! I was particularly surprised that mine came back but the MIL's didn't, she is in the West Kootenays, BC.

Not hold my breath that next year I'll have such luck though, enjoying them while I can!

Passionate Thumb, did I omit anything? Careful here. I have written two articles on the subject, and it might be a little more than what you ask for. But if you'd like, you can send me an email with your email address and I can send them to you as an attachment.

Rick

Hmm, I dunno, Thumb/PT...
I'm struggling with your idea, as it seems to suggest that "out-of-zone" plants that successfully winter over have somehow predicted what the winter will be like, and that they have somehow "learned" the appropriate level of hardiness in that first season. It is quite likely that I am misinterpreting your meaning - read on, and explain further, if necesary.

Your idea, as I interpret it, would seem to imply that the plant, during the portion of the first season that it is in the ground (no matter how brief that may be), was somehow "stimulated" to expect a zone 3 winter (without, presumably, ever having previously gone through one), and therefore went about preparing itself successfully for it somehow (and in some way differently than how it would respond to the onset of a zone 6 winter). Since what we think of as perennials (as opposed to woody plants) mostly die to the ground, it's unclear to me what sort of "preparation" would be useful in this case; any such preparation that changed the "properties" of the above-ground portion of the plant would be wasted effort, since it will most likely die to the ground anyway. Whereas, with woody shrubs, a prolonged gentle autumn allows new wood to harden off and the various chemical changes to occur (that generally result in good fall color), I haven't noticed that fall conditions make a difference to the survival of "out-of-zone" perennials. They either seem to be hardy or they're not (and I don't mulch, so that is not a factor).

If your second point about "understanding the biology" of the plant is intended as essentially a restatement of the previous observation (that it is important that some plants be provided with specific conditions of drainage/pH/moisture/exposure or other), then I would agree. A plant that is struggling to survive in less-than-favorable conditions will have a decreased chance of wintering over, I'd say. But, again, if I have misinterpreted your meaning, please elaborate.

It makes more sense to me to think of winter hardiness as a trait bestowed by the evolution of the species, which may have taken place in harsher conditions, perhaps, than that of the current climate in the area of its current range. Plant species are, in some cases (perhaps usually?), ancient; there is evidence that the ranges of some have been altered by ice ages and that others have "witnessed" and taken part in (i.e. had their ranges changed by) continental drift. (The occurrence of plant species is one of the lines of evidence used to bolster the theory of continental drift.) I think it is quite likely that zone ratings simply go on the current range of occurrence of certain plants or even, sadly, ignore those, e.g. Agastache foeniculum ("zone 6" in Readers Digest A-Z Encyclopedia, and my favorite published example of total ignorance of natural range, by the way) - and so when we find that South African or Mediterranean species are hardy here, it is a surprise. However, I think the hardiness of these species is an expression of their evolution in harsher conditions than currently occur in their ranges.
I find it hard to imagine that plant species are able to anticipate, or respond to, or prepare for cold conditions, unless they are evolutionarily-enabled to do so. Does that make sense? Please comment with your thoughts, anyone who is still interested in this thread!

Rick Id be interested in reading your articles, if you would send them to me, please.
By the way, with respect to some of the species mentioned
I grew Darmera peltata for many years in totally inappropriate conditions a dry spot under a tree where it kept coming back doggedly (though it certainly wasnt happy; unfortunately, I had no where better to put it at the time), so I have no reservations about its hardiness here.
From our brief experiment (1 year) with Chamaecyparis nootkatensis pendula, it seemed not totally suited to Calgary conditions - either the general low humidity or the drying effect of the Chinooks did it in, as it was pretty crispy in spring. Not sure if it was totally dead (but a sort of "mercy killing" seemed in order, as it would have been horribly deformed anyway).

I'm with ABgardeneer on her take of things, but there is another viable "option" PT may be alluding to:

It has certainly been proven thousands of times that cold hardiness is a function of many environmental factors, not just temperature. And that those determining factors are variable dependent on the species, and even on other environmental factors present for the same species.

For a simplistic example, Chamaecyparis nootkatensis 'Pendula' is perfectly temperature hardy at least to -35F(-37C), but at this temp, the dry winter winds and strong winter sun desicate it in the high mountains, western interior and midwest(where I live).

I say a "simplistic" example because interactions of environmental factors (and internal changes resulting from them) usually are very complex, and include many factors similtaneously. I don't know if anyone claims to know these well, as it changes greatly from species to species. This is probably one reason for a wide variety of zone ratings for the same plant: in one part of the country with xyz conditions, it is hardy to a certain temperature, while in another area with a different environment it is hardy to a different temperature limit.
I do however, strongly believe that changes in above ground parts of perennials have great effect on below soil line portions of plants, even though the former dies back.

And I agree, that at least for the most part, that a long unvaried fall will increase the winter survival of marginally hardy plants. Whereas some species are stimulated to harden for winter by photoperiod, and some by temperature, and some by other factors, few are exclusively prompted by just one. Therefore, I believe a long fall season will have a desiring effect on nearly all marginally hardy plants.

AB I think you observe correctly in that fall color has no effect (at least directly) on winter hardiness, although it might sometimes be an indication of same. Though I am not completely certain about this, I speculate that because the leaf abscision layer is forming at the same time and preventing free exchange of substances, effects on other plant parts or processes therein would be nil.

Now I've got to get out and round-up some lawn for a new garden I'll be starting next week, and uncase some troughs I made this past Sunday. I still need to scan the articles, but I'll get them out to you soon Lori.

Rick

Leftwood, the viable option you wrote about is related to what I was trying to communicate.

As an analogy lets examine a bacteria cell. In it's normal metabolic and physiological state that bacteria may be able to handle temperatures between minus thirty and plus forty degress centigrade. If that bacteria cell has encapsulated itself in/as an edospore it can withstand much greater extremes. The extracellular conditions can cause a change in the intracellular conditions. For example a low concentration of water outside the cell wall or membrane could force solutes to the interior of the cell. The presence of these substances or chemicals could free up genetic repressors which will change shape because of different chemical bonds. No longer repressed the genetic code is read and the cell will produce compounds that build up the endospore. This is an example of inductable operons but they could be repressible and accomplish the same thing if solutes exited the cell (or were somehow metabolically consumed).

Evolution is the key here as it has developed these measures to promote increased survival and reproductive rates of the species. Obviosly the bacteria cell does not want to go dormant when it can thrive and multiply without the protection of an endospore. Thus evolution has equipped the bacteria cell to rely on more then one condition (conditions that usually transpire concurrently) so its response can be more appropiate.

I'm implying (and that's the important word) that when plants are exposed to the conditions they have adapted to their triggers to produce antifreeze or whatever protects them (their endospore if relating to bacteria) are more likely to be pressed and because of that the plant will have an increased chance of survival.

I didn't mean that the plants "predict" a zone 3 winter or prepare for a zone 3 winter but that they can be triggered to prepare for a winter and that will increase their survival.

The timetable would be very different for plants because of the interaction between cells and the decreased surface area exposed to the environment per volume of cell(s).

I haven't read this so it isn't fact, although I did use some genetic knowledge to formulate my "idea". If you still feel I'm wrong or you see something missing feel free to tell me.

Hhhmmmm A good experiment would be to keep marginally hardy perennials indoors over part of winter then plant them outside (maybe by burying the pot) in the coldest part of winter and see if they have a decreased survival rate as compared to the same type of perennial that has been outside all year. if the survival rate is reduced then maybe the plants do need to "prepare" or harden off for winter.

PT,I am in complete agreement. In fact, that is how I initially understood your post to be. When AB replied introducing a different idea, I thought I had missed something, and that is why I said I agreed with "her take on things".

Your bacteria analogy was on the spot, and I found it very interesting about solutes being possible genetic repressors. It had nevered occurred to be before.

Rick

Has anyone tried Kalimeris pinnatifida (aka. Asteromoea mongolica or Japanese Aster)?

I notice that Heritage Perennials says that it's hardy in Zones 5 - 9, but Larry Hodgson in Perennials for Every Purpose says that it is hardy in Zones 3 - 9.

Thanks,
Sharon

Interesting comments, PT and leftwood...I'm still thinking them through...

Sharons2, I haven't grown Kalimeris pinnatifida, but planted Kalimeris yomena 'Shogun', a variegated green-white variety, last year and it wintered over well - no sign of flower buds yet though.

Another pleasant surprise was Kniphofia 'Royal Castle' (or, sometimes, 'Royal Castle Hybrids') - I bought 3 well-established plants in 4" pots last year (2 crowns each, if I recall correctly), and planted them in a relatively sheltered spot on the lee side of the house. They wintered extremely well, and have flourished since, with each plant now consisting of multiple crowns. The flowering was respectable (2-3 stalks per plant in early summer over a few weeks); the flowers were maybe not quite as bright as I might have wished - orange with yellow - but interesting. I had previously grown K. uvaria from seed, but rotted them out in spring (by leaving mulch on for too long). The 'Royal Castle' "strain" (as I've also seen it referred to) seems to involve K. uvaria but not sure of what other species.

This is such a good read and has so much information that I thought it worth bumping back up again.

I'm so impressed. You should write a book about the REAL cold zone plants. (I'd buy it!)

Has anyone tried overwintering Marrubium rotundifolium (Silver-edged Horehound) or Ruta 'Jackman's Blue' (Rue) in the ground? They are both supposedly zone 5.

Sharon

Thanks for resurrecting this thread, Pudge. You're right, it is a very interesting read.
It made me sad though, to see how many regular posters have disappeared from this forum.

I have a rue which I'm always happy to see return, it's probably at least 5 years old now. Not sure if it's Jackman's blue but it is blue-ish. One of my fav plants but I think the label has gone. It's at the edge of the patio so gets a lot of snow cover which probably helps it.

I also have a Munstead Lavender, last one of three, but it's still hanging on. Think I'll move it next spring to a better location.

I don't really try to push the zone here as I hate to see things die. However, I have the feeling you may all be a very bad (good) influence and I may have to try a few different plants. :)

Hmmm. Okay. How about Geranium 'Mavis Simpson'?

I'm interested in deliberately creating microclimates. I'm in zone 1, but through windbreaks, shelters, soil amendments, cold-frames, cloches, thermal mass, positioning for maximum insolation, location near ponds or other bodies of water that can ameliorate low temperatures, we fake zone 2, 3 even 4. I'm interested in how you create a warmer microclimate in your gardens.