New Japanese Maple Bonsai

Hello

I'm going to start a bonsai from a 2 -3 year old Japanese maple that I purchased from a nursery a couple years ago. Originally I was going to begin training it this past spring however I decided to let it grow another season before I started cutting it back, hoping to give it more roots and slightly thicker trunk.

The conflict I'm facing today is that currently it's fall and winter is just around the corner. Living in Ontario, it gets cold and depending on the year we can have alot of snow. I've been reading that people leave their bonsais outdoors...does that apply to Eastern Canada also? I'm concerned the pot would not provide the same kind of insulation as the ground did (the tree survived 1 winter planted in the ground last year).

Any thoughts are welcomed!

No image was posted... the tutorial may help.
https://ibonsaiclub.forumotion.com/t243-tutorial-on-posting-pics

Is it still in the ground, or in a pot?

Lady in Red wrote:I'm going to start a bonsai from a 2 -3 year old Japanese maple that I purchased from a nursery a couple years ago. Originally I was going to begin training it this past spring however I decided to let it grow another season before I started cutting it back, hoping to give it more roots and slightly thicker trunk.

The conflict I'm facing today is that currently it's fall and winter is just around the corner. Living in Ontario, it gets cold and depending on the year we can have alot of snow. I've been reading that people leave their bonsais outdoors...does that apply to Eastern Canada also? I'm concerned the pot would not provide the same kind of insulation as the ground did (the tree survived 1 winter planted in the ground last year).

Japanese Maple roots need to be kept above 15F or so - else they will die. Snow, per se, is not a problem and, in fact, it can be helpful to protect the roots. Burying your pot in the ground for the winter is one possible solution. Another possibility would be to build some kind of cold frame for it. And yet another, possibly simpler one would be to put the tree in an enclosure like a tool shed or garage (and be sure that the soil in the pot does not dry out).

London, ON is poised on the edge on hardiness zones 5b/6a [bless those nearby big lakes!]. With a little preparation and custodial activity your tree will be fine through winter. Do NOT bring it inside. It must have at least 100 days of dormancy to survive. I've heard people [that I respect] talk about forcing a false spring after 100 days by bringing a temperate indoors & putting it under lights. But i have no direct experience with that technique.

Once the tree is in a pot, the roots are more susceptible to cold damage. The ambient air is significantly colder than the ground temperature & that will easily penetrate through the pot to the trees roots. Either bury the pot in the ground approximately rim deep and then mulch up above that a few inches, OR place the pots on the ground [without burying] then mulch around and up over them [again, a few inches above the rim]. If you go the mulch-only route, do not leave the tree on a stand or raised backyard deck --- again, ambient air penetrating from below.
Toward protecting the branches, choose the most sheltered corner your yard affords. You don't want them exposed to the burning, drying effects of the winter winds. Along a fence, beside a shed or garage, etc. As well, use the shadiest corner available. With a southern exposure & all that sun, unusually warm weather can provoke a premature break of dormancy. Once the sap starts its [assumed] springtime flow the tree is vulnerable in case of a return to real cold weather.
If you don't have a sheltered, shady corner consider gerry-rigging something with burlap or mulching up higher [a friend builds a chicken wire cage around his favourite tree and mulches almost to their apex. Another friend puts his trees into large plastic storage bins, with a few holes drilled in the bottom for spring drainage, then fills with mulch --- one needs to make sure the vessel is big enough to provide room for mulch around the pots near the bottom].
Snow is your friend. It insulates and and provides the tree with that rumour of moisture it needs through the winter season. The fluffy stuff is best --- so if it doesn't naturally accumulate in the spot you've nested the tree, carry some over periodically.
All this applies to a potted tree. If it's in the ground and survived the winter foregoing, you're doing something right. If it's going to stay in the ground another winter, consider mulching up a bit for insurance & ensure there is snow cover in its proximity.