Lets talk winterizing

[Redcoat]

Hi all, been a while since I've posted, been busy with the new house, setting up, unpacking and all the fun stuff that comes there with. Anyway, got my little bonsai haven set up on my little wedge of deck (thank you wifey lol) so been doing all the tinkering of seeing how the light patterns are and the summer growth has been explosive to say the least, good morning to early afternoon sun and shade after that. But that's not the main point of this thread. It seems that this topic no matter how much google searching I do has too much specifics geared toward winter prep and continued winter care.
A little background as to why I feel this needs some discussion and debate on techniques and their pros and cons.
I had an awesome Chinese elm I bought last spring, potted and pruned over the course of the start to the growing season. So I did it slow as to not have a large stress to the tree but gradual little changes. Pruned to shape. Gave it a week. Did the little wiring it needed. Waited a week. Did another prune to balance out for the root work and repot so the vigor was fairly balanced. Over the summer I swear it grew faster than I could prune it. It was happy and vigorous.
Then came the fall. Started slowing down the watering and fertilizing as the temps dropped. Once it started hitting low 40 high 30s consistantly I moved them to the garage (this was in my apartment before I moved, the doors had a row of windows so I kept them out of direct light at all times, on a rack in a corner, and had a thermometer in there where the average temp was about 41°f. I also did a once monthly fertilizing using Ho Yoky Hy 0-10-10, and only when watering, light as it was, was needed) So as the usual dormancy went, the leaves dropped and come spring as temps started to hit the upper 40 to low 50 I brought the trees back up. Except the tree never woke back up and was a dead twisted stick. All my other trees (cluster of 5 red lace maples, English boxwood, Japanese larch and hokkaido elm went back to work)
So heres my question. What might I have done wrong? I am and when I moved, been in zone 6a. I have since acquired and made a nice replacement elm (I'll add pictures at the bottom) and want to hear what you all do as the time approaches all the way thru winter until spring. What's some tips and tricks? My house has a 2 car detached and non insulated garage. I was thinking to use those under bed storage totes ( about 6" deep) and surrounding the pots with mulcj. I bought the first one and the replacement both from the same local bonsai nursery (it's technically in zone 6b) and when I asked how he winterized, told me just puts them in a cold frame. I didn't ask about winter fertilizing tho. So maybe that's a possibility, that my garage wasnt cold enough, it didn't go dormant really? I want this one to survive as well as the shohin size one I just got from someone in Michigan where thats, zone 5? 4? Possibly 6a like me? But enough with the tangents. What's some good advice with these trees? If you couldnt tell, they are my favorites lol
Oh and heres the one, I'll add pics of the other one tomorrow. But for now it's the before and after picture

 

[Josiana]

Could it be that you did too much work within such a short time period that the tree spent all of its energy to recuperate, and could not save any thing for dormancy?

Usually people just do one 'major' bit during a single growing season.

 

[JudyB]

If your your other trees listed survived the winter, then it wasn’t lack of dormancy, as they also need a dormant period. Hard to say what killed your elm, could have been many things, from disease to root issue, maybe even rodent damage overwinter. Be careful how much you water, only water when they need it in winter.

 

[Redcoat]

Yeah I was diligent and very light with the watering. I'm wondering if it was the fact I didn't have it in a cold frame where it got the full temp drops and swings like it was used to at the nursery and it got warm too much in the garage at the apartment? It was am elevated building on a hill and the garage was actually in ground so it was insulated and didn't get like I said below 41. I did do a thorough once over before removing it and no rodent damage. So I was a little stumped. Ah well hopefully this one does better.

 

[Redcoat]

Could it be that you did too much work within such a short time period that the tree spent all of its energy to recuperate, and could not save any thing for dormancy?

Usually people just do one 'major' bit during a single growing season.

This is true but honestly the only major work was the foliage prune back and a few wired branches. The repot was more of a pot slip than anything it was already in a nursery pot with bonsai soil. I just pruned of a few roots sticking on the outside soil to fit the pot better and was done during spring as it was waking up before it really started to grow. Like I said it exploded with growth all summer and no major work just some directional pruning was done during the summer. I try to limit my wiring, I dont like the risk of wiring scars even of they can heal.

 

[LanceMac10]

In the future.....no slip-potting!!!!!!!!!!

 

[Redcoat]

I only did it due to the fact it's reporting was done at the nursery early spring and I bought it middle of spring. I didn't see the need to rake it out again to put it back in bonsai soil since it already was. I just added the middle but needed after removing a few stray roots and to fill in the pot. But usually I don't slip pot

 

[sparklemotion]

I have read many many conflicting things about "dormancy" for ulmus parvifolia.

But, I would guess that 41F was too cold for your elm.

Based on one whole winter of keeping a pomegranate alive, (according to evergreen garden works they are in the same category), I would leave your new elm outdoors until leaf drop then bring it in somewhere where it will stay close to 60F for the winter. Give it light if it starts pushing leaves.

For me this meant living in a window well in a basement area that is kept at 62F most of the time, unless someone is watching TV in which case we heat the room to about 68-70F. I didn't precisely monitor the temperature in the space where the pomegranate hung out, but I wouldn't be surprised if it were closer to the mid 50s for the vast majority of the winter. It did start pushing in late winter, but I had space under my grow lights to support it. The growing shelf stayed closer to 70F.

 

[rockm]

I think it probably dried out. Chinese elms are pretty tough plants, though...

Watering in the winter is tricky in a sheltered storage place like a garage. Things can go dry easily. Also, dormant trees don't need ANY fertilizer. It's a waste of time to apply it when trees are dormant.

Also, I'd allow the tree to get hit repeatedly by frosts and early freezes in Oct.-Nov. before bringing it in the garage. those are important in its dormancy cycle, hardening off the roots for the winter.

 

[rockm]

I have read many many conflicting things about "dormancy" for ulmus parvifolia.

But, I would guess that 41F was too cold for your elm.

Based on one whole winter of keeping a pomegranate alive, (according to evergreen garden works they are in the same category), I would leave your new elm outdoors until leaf drop then bring it in somewhere where it will stay close to 60F for the winter. Give it light if it starts pushing leaves.

For me this meant living in a window well in a basement area that is kept at 62F most of the time, unless someone is watching TV in which case we heat the room to about 68-70F. I didn't precisely monitor the temperature in the space where the pomegranate hung out, but I wouldn't be surprised if it were closer to the mid 50s for the vast majority of the winter. It did start pushing in late winter, but I had space under my grow lights to support it. The growing shelf stayed closer to 70F.

41 is far too WARM for dormancy. Chinese elm can take cold temperatures, especially if they are allowed exposure to frosts and freezes on the benches through mid-Nov. before being put into storage. I've done this for years here with my Chinese elms. I mulch them into a cold pit at Thanksgiving after leaving them out through the first frosts and freezes in Oct.-Nov.

 

[sparklemotion]

With all due respect, @rockm, I'm not sure we're talking about the same 41F. @Redcoat was seeing an *average* temperature of 41F, whereas, (microclimates aside), Google tells me that the average high temperature in Fairfax, VA is never lower than 41F. Even if your trees get some freezes, they are still going to be seeing temps higher than 41F for most of the winter. That isn't necessarily analogous to @Redcoat's situation.

Remember that ulmus parvifolia is native to places that don't get anywhere near freezing -- Taiwan, India, etc., and we are keeping them in tiny pots.

 

[bonsaidave]

I lost a couple collected saplings from not watering enough last winter. One was an elm. This winter I will be watering more often.

 

[Cable]

This thread is relevant to my interests. I lost something like 6 trees last winter keeping them on the ground between the house and garage while covered in leaves (and two were in window wells). This year I plan to put the deciduous in my root cellar (stays right around freezing) and leave the evergreens outside (I didn't lose a single evergreen).

 

[sorce]

no slip-potting

Could be the ugly, yella, hiding culprit itself.

That caused the

dried out

Which sounds most likely.

....
My trees have stayed out, or just on the ground.
I get to -20F with no snow.
Hover around freezing with about 17.8 billion freeze thaw cycles a DAY thru winter..
Keep em saturated...
And NEVER lost an elm solely due to winter.

Have killed, lets say...28/30 though...lotta experience!

Even that weak, winter has never killed one wet.

FTG!

S

 

[rockm]

With all due respect, @rockm, I'm not sure we're talking about the same 41F. @Redcoat was seeing an *average* temperature of 41F, whereas, (microclimates aside), Google tells me that the average high temperature in Fairfax, VA is never lower than 41F. Even if your trees get some freezes, they are still going to be seeing temps higher than 41F for most of the winter. That isn't necessarily analogous to @Redcoat's situation.

Remember that ulmus parvifolia is native to places that don't get anywhere near freezing -- Taiwan, India, etc., and we are keeping them in tiny pots.

Good lord. I have no idea what you're looking at but we get lows WELL below 40 in the winter. We get sub zero F in Jan. and strings of below 20 F for days in Jan. and Feb. We get snow, sometimes ALOT of it

There are a couple of Chinese elms under this 15 inch deep snow, alongside the larger cedar elm and Bald Cypress. This is my 25th winter with Chinese elms...

Ulmus Parvifolia is hardy zone 4-9. It can well handle freezes and frosts. It is a wide ranging tree in Asia and native to more than a warm tropical climate. Keeping it warm in the winter leads to continued growth--which is you're keeping it in a sheltered indoor location can mean it needs light. Babying it with indoor warm conditions (especially in the house) leads to bad things.