chinese elm - converting one to full dormancy

hey all, from what i understand, chinese elms can go either way re: dormancy or not... with the first winter depending on what it is used based on where it was originally from...

a couple years ago i got one that came from down south (brussels nursery) and so i assumed it didnt go into deep dormancy, so for the 1st winter i kept in inside in full light and it was ok... mopey and leaf droppy the whole winter, but come spring, it was ok... not great, but ok (and that could be attributable to our much cooler than normal spring and summer)

anyways, this year i am going to try to convert it to full winter dormancy...

my thought (which is also based on suggestions i have heard) is to leave it outside until she drops all of her leaves and then shelter it in the garage with the rest of my deciduous... the garage is not heated, but it has south facing glass block windows, it is insulated and it has supplemental warmth from 2 hot cars being pulled into it every night... and after last winter, i invested in a heat mat and thermostat system that turns on at 32 F. and off at 33 F.

does that sound like it will work for converting this tree to yearly dormancy ?

In my experience Chinese Elms don't go dormant like other deciduous species, at least not in the UK, and I suspect they don't actually need this. Mine drop their leaves at random times during the year but keep on growing throughout. I think if you try to force it to be dormant there is a risk of damage, better to leave it outdoors in a sheltered spot and let it do its own thing

Dave

with our winters, if i left it outside, i might as well just skip a step and chuck it straight into the fire

input appreciated, but i believe many in this part of the US go fully dormant.

Hey Kevin. Chinese Elms are sub-tropical and need to be treated as such. I lost two smaller ones this winter that were housed in my cold frame/front porch. A larger one I have was brought into the house before a long cold spell and survived and grew well in the spring. I'm pretty sure we have similar climates and your right, leaving a Chinese elm out over the winter would turn it into tanuki material. Still, it needs dormancy. Growing year-round will exhaust the tree and lead it on a downward spiral. It would probably still grow, but not as well if given a period of dormancy. I believe if you can keep the plants in the temperature range you indicated, they should survive and prosper. For what it's worth, I attended a lecture this past weekend on winter care at New England Bonsai Gardens this past weekend and the first piece of advice was...wait for it....move south!! And really, he's not wrong!! It's tough to grow a tree in a container in a zone 5 climate, as you well know! The thaw, freeze cycle will do a number on a Chinese elm's fleshy roots. No offence to ironhorse, but the UK might as well be Hawaii compared to zone 5!! Twenty straight sunrises at 0 degrees Fahrenheit says it all, I believe....

I have 3 cork bark a seiju and a regular Chinese elm. I keep them in a shed frozen all winter. Solid. My trees all came from N. Carolina and did fine their first winter here. Although they drop their leaves last of all my elms. First to open in spring too.
I keep trees in containers in zone 4 just fine. No losses last year even. The trick is to let them freeze solid and to try to keep it like that. It's the thawing then freezing then thawing then freezing that does them in.

Though some of the cultivars are less hardy, then species, Ulmus parviflora, is cold hardy to usda zone 5. Mine have frozen solid and seen temps well below freezing every winter...and I've had them since I lived in MA. Personally, I would treat them like your other deciduous trees...let them experience the initial cold of early winter, then bed them down in your garage for the long haul.

sounds good all,,, and thanks !
i was pretty much looking for confirmation of what i had heard
and what i reckoned was the right way to approach this.

farkin' winter

thank gawd for snowboarding, snowshoeing, home cherried brandy and fire-pits !!!
but last winter there was precious little of that even...
(except the brandy)

I kept my ch. elm in an attached garage after it lost its leaves, no suppl. heat, 6 inches of root showing(root over rock), and two inches of soil. It woke up happy and hungry.

right on david... i'm sure that 1st winter was worrisome

but yeah, i knew they can do it... i was just worried about "converting" one...
i suppose i could have concocted some type of "kool-aid" mixed with holy water and a touch of hyperbole,
but i think the normal way will be better for once...

Sorry, I didn't mention that the local nursery keeps their 'soft' deciduous bonsai in a part of their greenhouse that stayed generally 50's to low 60's through the winter. That's where I bought it. I didn't attempt any 'conversion'- it was cold turkey. Though there is so much disagreement on this subject in general, pretty much everyone states that when kept inside during the winter the ch. elm pretty much sucks hind tit all the time. That tells me it lives just a little weaker without a hibernation, so I would venture a guess that the only real concern is how weak has your tree been looking. If weak, take it easy one or two winters to see if it perks up. If strong, boot it out of the nest.

Precarious wrote:pretty much everyone states that when kept inside during the winter the ch. elm pretty much sucks hind tit all the time. If strong, boot it out of the nest.

spoken like i true nebraskan !

thanks !

My chinese elms keep their leafes all winter, my japanese elms drop theirs, they are kept the same way.
To me does it not look like this is something people can alter from elm to elm.

Kind regards Yvonne

Where was the origin of the Ulmus in question Kevin? If you know that is. That will directly effect is overwinter/dormancy responses, it also is something that cannot be modified.

Like I said earlier Kevin. I live in zone 4. I got 5 Chinese elm cultivars from North Carolina. They are the last to drop their leaves but they all turn in the fall and drop off. I didn't do anything special. Just left them out with the rest of my trees. And they froze solid and stayed that way for months. It was fairly cold here last winter so where you live it should be downright tropical in Beer City. I would keep them in your garage but shade the south facing window for fear of it getting warm in late winter early spring and coming out of dormancy too early. These will start to grow at the drop of a hat (or beer goggles if you prefer). Mine did that to me last year and then we had a hard frost that killed all of the leaves. Total defoliation. They recovered though. Also the cork bark varieties are tougher than the smoother barked kind.
If you can keep a juniper or Japanese maple alive through winter you can keep these alive too.

thanks again M.

when i installed the glass block windows, i made sure to get ones with vents for just such an occasion.

no longer worried about it...
just gonna put it to sleep with the rest...

along with this thread

Kevin,

word of caution. My elms sleep due to the shortening of days and start to grow when the days begin to grow longer.
My friend in Cannon Falls, kept his in an unheated room, but it never froze.
So a safe temperature might be below 55 deg.F ,but above 40 deg.F.

Normally you test these ideas on expendable root cuttings from Spring, left outdoors for the year.
Best of luck.
Khaimraj