Chinese Elm Dormancy?

Redwood Ryan

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Hey all,

I have a question about dormancy with Chinese Elms. I've read online that they can go up to 2 years without needing a rest at all. Does anyone have experience with this? The reason I ask is because I picked up this Chinese Elm from a nearby nursery. It is supposedly from "Florida" and arrived at the nursery in full leaf. I must keep it indoors, but I've been wondering if I should force it into dormancy somehow, or if I should just let it go for this year and let it rest next year. It is in desperate need of a repot too. Thanks!

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And I plan on layering this tree before the first bend, in case anyone was wondering....
 

Smoke

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It may be from Florida but it was trained and grown out in China. In my climate elms grow all year long. Catlins and contorted lose their leaves but the standard elms keep leaves all year long. In the winter they "exchange " leaves by turning yellow and the new leaves will push the yellow ones off, much like my pyracanthas do. Since the leaves are so large on pyracanthas I defoliate them and get better budding. Elms would probably benifit from this also but now would not be the time to do it.
 

Dav4

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Dormancy is only beneficial if it satisfies a plant's chilling requirements, and it takes months for temperate plants to enter dormancy each year. "Forcing" dormancy on a tree that you will probably want to be outside and growing in 2 months isn't a good idea. Get it outside when weather permits, then let it go dormant outside next fall.
 

Redwood Ryan

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Hmmm thank you both very much! Would you recommend I go ahead and repot since I can't repot it when its buds are popping?

And here is where I am going to air layer:
p.jpg
 
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rockm

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but I've been wondering if I should force it into dormancy somehow,

Why on earth would you do that with spring a month away? You cannot "force" dormancy. The process to enter and sustain dormancy takes months, not weeks...A tree artifically "forced" into dormancy is really just shocked into stop growing. Even if you succeed in forcing it, it would require a month or more of chilling in someplace below 40 F. When it emerges from dormancy, it will face a shortened growing season outside, possibly not long enough to produce a crop of leaves and prepare for the coming winter. The end result of all this could be a winter -killed tree next winter.

Even if it needs a repot, the time to do it has passed for this year. You could slip pot it into a larger container without disturbing the roots if you're really concerned....You could be really agressive and root prune now, but you would have to defoliate the tree entirely or substantially...

Repotting it now would delay an air layer. If you plan on air layering the top (which isn't really worth the time and effort IMO), you should plan on doing that next year, THEN a repot the FOLLOWING year. The more root mass present, the better the chance the air layer will go well.
 

Redwood Ryan

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but I've been wondering if I should force it into dormancy somehow,

Why on earth would you do that with spring a month away? You cannot "force" dormancy. The process to enter and sustain dormancy takes months, not weeks...A tree artifically "forced" into dormancy is really just shocked into stop growing. Even if you succeed in forcing it, it would require a month or more of chilling in someplace below 40 F. When it emerges from dormancy, it will face a shortened growing season outside, possibly not long enough to produce a crop of leaves and prepare for the coming winter. The end result of all this could be a winter -killed tree next winter.

Even if it needs a repot, the time to do it has passed for this year. You could slip pot it into a larger container without disturbing the roots if you're really concerned....You could be really agressive and root prune now, but you would have to defoliate the tree entirely or substantially...

Repotting it now would delay an air layer. If you plan on air layering the top (which isn't really worth the time and effort IMO), you should plan on doing that next year, THEN a repot the FOLLOWING year. The more root mass present, the better the chance the air layer will go well.

Well Rock,

It had been suggested to me on another forum that I should force it into dormancy by placing it in a dark room. A fridge was also brought up. I was told by someone on that forum that they had repotted their indoor chinese elm and it didn't even skip a beat. It kept on growing. So I'm sure it won't be too deadly to repot it without pruning and then keep it in a sheltered location.
 

Smoke

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Ryan, I am sensing you are not understanding the life cycle of an elm in temperate climates. Not all trees need such an extensive dormancy period. Elm is one such tree.

Forget dormancy this year and move on with it. Adjust your growing loocation next year to make sure it recieves the needed cold to get it there and then it will lose it's leaves.
 

Walter Pall

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My Chinese elm is in the cold greenhouse all winter. There temperatures go well below freezing for many days. But still the tree has most foliage until end of March. This happenes since 20 or so years and the tree is happy and will grow new buds by the end of March. I suppose the tree does have a clear dormancy period. It just does not know that it is supposed to be a deciduous tree. You can not tell whether a Chinese elm is dormant by just looking at the foliage.
 

Redwood Ryan

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Ryan, I am sensing you are not understanding the life cycle of an elm in temperate climates. Not all trees need such an extensive dormancy period. Elm is one such tree.

Forget dormancy this year and move on with it. Adjust your growing loocation next year to make sure it recieves the needed cold to get it there and then it will lose it's leaves.

I suppose not, I was just told that this tree MUST go into dormancy or all hell will break loose and the tree will die.

My Chinese elm is in the cold greenhouse all winter. There temperatures go well below freezing for many days. But still the tree has most foliage until end of March. This happenes since 20 or so years and the tree is happy and will grow new buds by the end of March. I suppose the tree does have a clear dormancy period. It just does not know that it is supposed to be a deciduous tree. You can not tell whether a Chinese elm is dormant by just looking at the foliage.

Thank you Walter, that is good to know. I won't worry about the dormancy this year.
 

Smoke

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I suppose not, I was just told that this tree MUST go into dormancy or all hell will break loose and the tree will die.



Thank you Walter, that is good to know. I won't worry about the dormancy this year.


I would start relying on some new friends....
 

greerhw

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I kept a big one in my garage during the winter for several years before I sold it. My garage never got below about 40 degrees, it would drop it's leaves. Some years it would put on new leaves in March in the dark. They're pretty tough.

Harry
 

rockm

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"Well Rock,

It had been suggested to me on another forum that I should force it into dormancy by placing it in a dark room. A fridge was also brought up. I was told by someone on that forum that they had repotted their indoor chinese elm and it didn't even skip a beat. It kept on growing. So I'm sure it won't be too deadly to repot it without pruning and then keep it in a sheltered location."

Whoever told you this has no understanding of how temperate trees work. Dormancy cannot be induced by placing the tree in a dark room or by throwing it into a refrigerator. Both treatments simply shock the tree into inactivity, which is NOT dormancy. It's the same thing as hitting someone in the jaw, knocking them cold and calling that "sleep."

Yeah, you can repot a chinese elm when it's in leaf, BUT YOU BETTER UNDERSTAND HOW THE TREE FUNCTIONS before you do that. It will "skip a beat" in growth, especially since you will have to keep it inside and frost free until the end of April around here. If you remove old soil (but not root pruning) and replace it with new, you will disturb the root mass enough to compromise the tree's ability to function to a certain extent. Of course, chinese elm is a very resilient species and can take a lot of abuse, so it may live on in spite of what you do to it.
 

Redwood Ryan

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Whoever told you this has no understanding of how temperate trees work. Dormancy cannot be induced by placing the tree in a dark room or by throwing it into a refrigerator. Both treatments simply shock the tree into inactivity, which is NOT dormancy. It's the same thing as hitting someone in the jaw, knocking them cold and calling that "sleep."

Yeah, you can repot a chinese elm when it's in leaf, BUT YOU BETTER UNDERSTAND HOW THE TREE FUNCTIONS before you do that. It will "skip a beat" in growth, especially since you will have to keep it inside and frost free until the end of April around here. If you remove old soil (but not root pruning) and replace it with new, you will disturb the root mass enough to compromise the tree's ability to function to a certain extent. Of course, chinese elm is a very resilient species and can take a lot of abuse, so it may live on in spite of what you do to it.

Thanks! That is the whole discussion that ensued, whether or not temperature affects dormancy or if it is the amount of light. I'm debating the repot now...
 

greerhw

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If you don't ever remember anything else I ever tell you remember this, " Most Americans repot their trees to often". Advice shared with me from a bonsai master.

Harry
 

woodguy

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I was the one who stated on another forum that I had repotted mine a few weeks ago. I prefaced it though by saying that I figured the shock of the re-pot couldn't be worse than the awful soil that it was in. Although it was growing well the soil was posing a watering problem so I went for the repot. It's actually growing much better now and has put out new growth. Mine like Ryans was from "Florida" and hadn't seen dormancy this year. I'll let it go dormant after an extended season this year. I wasn't the one who suggested forcing dormency though. That would be a bad idea.
 

Mike423

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I agree on both subjects. I have heard or some Chinese elms grown in semi-tropical environments for a few years without any issues, so skipping this years dormant period wont be a problem. I would also not repot until next spring, unless it is extremely root bound then I would recommend simply up-potting it in a slightly larger pot, being carfull not to disturb the root ball.
 

Redwood Ryan

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I agree on both subjects. I have heard or some Chinese elms grown in semi-tropical environments for a few years without any issues, so skipping this years dormant period wont be a problem. I would also not repot until next spring, unless it is extremely root bound then I would recommend simply up-potting it in a slightly larger pot, being carfull not to disturb the root ball.

Thanks Mike, it is extremely rootbound so I may just slip pot it into some turface.
 
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