japanese maples frozen in pots

[Gilly]

so I'm new to this I hav about 6 bllodgood maples in my garage in pots that are insulated with leafs and pine needles surrounded by those leaf bags ,very cool but the pots seem to have frozen solid ! is this the end of my bonsai career before it began !!!

 

[0soyoung]

No.
The will probably be okay down to 0F/-18C.

 

[Dav4]

so I'm new to this I hav about 6 bllodgood maples in my garage in pots that are insulated with leafs and pine needles surrounded by those leaf bags ,very cool but the pots seem to have frozen solid ! is this the end of my bonsai career before it began !!!

Nope... palmatums can stay in frozen soil all winter long as long as the soil temps stay at or above 15F.

 

[Gilly]

ok good to know thanks dav4
can't wait to start learning more

 

[Soldano666]

I have Acer palmatum placed on the ground buried in snow with winter temps than can get below -10f

 

[rockm]

ok good to know thanks dav4
can't wait to start learning more

Would help tremendously if you would provide the region where you live. It's critical to have that to give accurate advice. What works in Florida won't work in Maine...
Tree roots freeze all the time in nature. It's the depth and length of the freeze that makes the difference for them. It's highly species dependent, each species of tree has its limits and its needs. For instance maples actually REQUIRE a period of cold dormancy to remain healthy. If they are not exposed to frost and freezing (within limits) they weaken and die...

 

[Deleted member 21616]

for what its worth, there are people in quebec who have e.g. deshojo and katsura planted in the ground, and at least for the first few years, the roots are pretty shallow. we have a +48" below ground frost line, and in november/december we normally get many spurts of several consecutive days of -30C (-22F) before any snow has fallen (i.e. before the snow insulated the roots). i don't know what the temperature of the ground is when the air is -30, but i can tell you that the loose soil in my vegetable garden is a 36" deep frozen block of ice from december to march

i would add that bloodgood (and sentinel? or something like that) is viewed as the most winter hardy of 'japanese maples' in quebec's box stores - its often the only variety they sell

been speaking to people more and more about growing maples in the ground in quebec, and i keep learning that jeff goldblum was right: life finds a way

 

[Gustavo Martins]

For instance maples actually REQUIRE a period of cold dormancy to remain healthy. If they are not exposed to frost and freezing (within limits) they weaken and die...

So I’ve been told. Yet, they grow in zone 11.

This is just one of several in a garden. It never freezes. No frost. Next to it you can a culture of yam. Oh well

 

[0soyoung]

Dry air and bright sun are the primary threat to acer palmatums when the ground/substrate is frozen. Lets add wind to that and the mix causes what is often called 'winter burn' - the cambium is killed on the south and/or windward exposed areas.

they grow in zone 11.

This is just one of several in a garden. It never freezes. No frost.

Even though we are talking about roots in frozen substrate/soil, I bet there are a fair number of hours there that air temperatures are below 8C, affecting a winter dormancy. I am convinced that some number of chilling hours are required for acer palmatum to survive.

 

[Gustavo Martins]

Even though we are talking about roots in frozen substrate/soil, I bet there are a fair number of hours there that air temperatures are below 8C, affecting a winter dormancy. I am convinced that some number of chilling hours are required for acer palmatum to survive.

No not that many... You see (below) 3.5 is the record low. It is usually much warmer. Coldest month (February) you get may 6C a few nights.

 

[Morax]

Had two in front of house where the temps would drop into -20s couple foot of snow etc (Pennsylvania winters) and they came back year after year with noone touching them. Then got wiped out from a fungus attack...

 

[rockm]

So I’ve been told. Yet, they grow in zone 11.

This is just one of several in a garden. It never freezes. No frost. Next to it you can a culture of yam. Oh well

View attachment 224550

FWIW, they may grow, but they don't appear to grow all that well. That tree looks a bit weak and parts of it look like they're in decline.

 

[Gustavo Martins]

FWIW, they may grow, but they don't appear to grow all that well. That tree looks a bit weak and parts of it look like they're in decline.

Maybe. I don’t know as I have no comparison. However, There’s more there that look better (fuller) and bigger. This one is rather exposed and that stream behind runs hot and ferreous water. Lots of humidity year around.

 

[Smoke]

I am convinced that some number of chilling hours are required for acer palmatum to survive.

What temp and how long. I don't get much chilling and mine thrive. Going to be 39 tonight and thats really cold for me. Average is about 42 for winter here.

 

[rockm]

Chilling hours required for dormancy can be in the high 40's and below. It doesn't have to be below 32.

 

[0soyoung]

What temp and how long. I don't get much chilling and mine thrive. Going to be 39 tonight and thats really cold for me. Average is about 42 for winter here.

The accumulated hours below something like 40-45F is what matters, not averages and not simply an exposure to temperatures below this threshold. The fact that you have an average low of 42 says that several hours every night are spent at temperatures below 40-45F

A demonstration that just about anyone can perform is to put one or more cuttings in a plastic bag with some moist paper (or what not) and put it in their refrigerator (just like one does to cold stratify seeds). Also make another 'package' like this and leave it laying around somewhere in your house. Check every now and then to see if buds have burst. Put the other 'package' in your refrigerator for a week, say. Then take it out of the refrigerator and let it sit at room temperature for another week, say - if no bud burst, put it back into the refrigerator for another week - rinse and repeat. Count the weeks accumulated in the refrigerator and in the room.

Maybe it will become the "Six Week Bust Your Buds Contest" if others join in.

 

[Gilly]

Nope... palmatums can stay in frozen soil all winter long as long as the soil temps stay at or above 15F.

so I'm new to this I hav about 6 bllodgood maples in my garage in pots that are insulated with leafs and pine needles surrounded by those leaf bags ,very cool but the pots seem to have frozen solid ! is this the end of my bonsai career before it began !!!

Wow you guys are good !!!!

 

[Gilly]

So I live in Ct , and I can tell you that the pots you see are basically frozen solid !!!!!

 

[Gilly]

So I live in Ct , and I can tell you that the pots you see are basically frozen solid !!!!!

Also how do you like my triple I have been twisting these 3 saplings ? !!! Is this frowned upon , have you seen this often ??? These I was told are blood good maples !

 

[Dav4]

So I live in Ct , and I can tell you that the pots you see are basically frozen solid !!!!!

Personally, I'd have these down on the ground with the pots mulched or insulated in some way. When I lived in zone 6 MA, temps in my unattached garage could fall into the single digits... all my trees where on the cement floor mulched with wood chips and did just fine. I monitored the temperature of the floor under the mulch and it always stayed at or above 32 F all winter. You will need to set out traps for mice and voles... juvenile maple bark and small branches are very attractive to them during the dead of winter.