Japanese Maple Sprouting New Growth and Leaves in September. What Should I do?

[atomic_sleep]

Hi Everyone,

I am new to the forum - hope this is an appropriate place for this, sorry if its not.

I have a potted Japanese maple (6 inches tall) that I dug out of my mother in law's back yard in the early spring, it is not yet a bonsai but I want to train it into one. I brought it inside where it came out of its dormancy and put out leaves. When the weather got warmer I put it outside for the summer.

It has been doing fine all summer but I just noticed that it has some new growth/leaves beginning at the top, it seems like it is a bit out of sync with the seasons...

I'm not sure what to do with it going into the fall and winter. Should I bring it inside before it gets cold and encourage the growth? What would happen if I don't provide the tree the right environment to go dormant? Or should I just let nature run its course and leave it out all fall and see what happens? I feel bad for the tree spending energy on the new growth only if it is to die off from the cold.

I live in Ottawa Canada so my original plan was to let it go dormant then insulate the pot and put it in my shed. Any advice would be appreciated.

 

[Paradox]

Keep with your original plan
Bringing it inside wont allow it to experience those cold temperatures it needs to go to sleep for the winter.

Seeing new growth in September after the hellish heat of summer (especially this summer) is normal.

When temperatures really do start to get cold at night (you may already be having this where you are) and cooler during the day, you'll see the tree start prepping for dormancy (leaves change color).

I wouldn't worry about putting it into the shed until temperatures start to get below freezing.
You want the tree to get frost and a mild freeze overnight is fine. This is how it knows its time to sleep.

Just remember in the shed you will still have to provide it with water once in a while so don't wrap the pot so that it doesn't drain.
Honestly not sure you really need to insulate it or how effective that will work anyway if the shed gets really cold (less than minus 10 deg F). What were you going to use to do that?

When I've kept mine in the garage, I had to water them at least once a week. Granted I'm much warmer than you most of the time in the winter. If the pot freezes solid though, you cant water obviously but you'll still have to watch with temperature changes

 

[SC1989]

Most of my trees keep growing until leaves change color. I think the cooler weather up north in early fall is like "second spring". You gotta be careful keeping it in your garage when it's below zero, if you aren't burying it in the snow.

 

[rodeolthr]

Totally normal in my climate. I get huge extensions on the branches and lots of growth once the heat of summer has passed.

 

[atomic_sleep]

Thanks everyone for providing valuable input, glad to know my tree isn't behaving abnormally! I will leave it outside for now.

However, some of your responses have begged a follow up question... To over winter this tree I was going to put this tree in a large container (along with some other trees) and surround the pots with mulch to insulate it, and place it in my detached shed, and of course water occasionally. Where I live it gets well below freezing in the winter (some days reaching -30C or -22F in the dead of winter). Would this protect it enough? I don't have a garage, the next best thing to the shed would be my unfished basement, but that wouldn't get anywhere near freezing.

 

[SC1989]

As long as you can keep the roots above 10-15 degrees F. I had to keep some palmatums in my attic last winter, once the deep cold sets in. If you do keep it outside, bury it in the snow. Cold dry wind dessication will get the tops

 

[Ininaatigoons]

The temperature is supposedly 15 degrees above zero for potted. 20 degrees is safer. When the nights start to get that low put it in the garage off the ground. It's amazing how warm it stays in a garage. Attached garage is even better. I keep a thermometer in the garage to keep an eye on the temps! When I know it's going to be very cold at the end of January and February I actually have to use a heater. It's always best to keep them between 20 and 40. Then in spring you'll get to do the dance. In the garage and out of the garage as the tree starts budding it gets really important to do it twice a day! The garage becomes too warm during the day and outside is too cold at night! One year I brought a tree in the house during this time and it leaved out fully. Once I brought it outside the leaves scorched because they weren't acclimated to sun. If you go that route you have to acclimate to sunlight.
If it's getting a second flush now there will be some dieback, but it should survive.