How Do You Overwinter Your Bonsai?

[99 Mile Creek]

Hoping to convince everyone to share their overwinter setups here with the community for ideas...or just to show off your setup.

As the breath of autumn comes into my region, I have to think about how to overwinter my topicals right about now (7SEP2025), temperatures beginning to dip past 50°F (10°C).

I've commandeered the bathtub in our bathroom, in the past, for my tropicals, placing a table inside it to hold my bonsai at window level, but my wife says, "Oh...no you're not," this year and purchased me a 4ft Vivosun grow panel for my early birthday present.

I'll have to figure out something to increase humidity in for them in the basement.

 

[Carol 83]

Our climates are very similar. My tropicals spend the winter inside under full spectrum LEDS. My deciduous hang out in my detached, unheated garage. I usually bring the trops in mid to end of October, letting them see some temps in the 40's but they are close to the house. Last year's indoor setup.

 

[Michigan Tree Murderer]

Hoping to convince everyone to share their overwinter setups here with the community for ideas...or just to show off your setup.

As the breath of autumn comes into my region, I have to think about how to overwinter my topicals right about now (7SEP2025), temperatures beginning to dip past 50°F (10°C).

I've commandeered the bathtub in our bathroom, in the past, for my tropicals, placing a table inside it to hold my bonsai at window level, but my wife says, "Oh...no you're not," this year and purchased me a 4ft Vivosun grow panel for my early birthday present.

I'll have to figure out something to increase humidity in for them in the basement.

I'm also in the basement. And I have way too many tropicals. I have a humidifier & fan in the room and that keeps them happy.

Pic from 2023.


I also have a grow tent. And separate Spider farmer lights and as mentioned before way too many plants.

 

[99 Mile Creek]

I needed to the light installed and adjusted in anticipation…and I dread the upcoming dance, back and forth. Only hitting 40s yesterday and tonight, then going back to 60s for our lows, so they’ll go back out for about three weeks—I do baby them a bit.

And what a beautiful setup! The window, in my opinion, makes that really work well. Very nice trees.

 

[99 Mile Creek]

I'm also in the basement. And I have way too many tropicals. I have a humidifier & fan in the room and that keeps them happy.

Pic from 2023.
View attachment 613336

I also have a grow tent. And separate Spider farmer lights and as mentioned before way too many plants.

View attachment 613338

This is amazing. I thought about doing the tent, too. Now I’m back in the fence about it.

Do you have the central ‘hub’ that controls lights and humidity and fans?

 

[Michigan Tree Murderer]

This is amazing. I thought about doing the tent, too. Now I’m back in the fence about it.

Do you have the central ‘hub’ that controls lights and humidity and fans?

Yes. The controls allow you to set temperature, humidity, light level, alarms, exhaust fan time & inline fan times. And it's all timed so you want 14 hours of light or 10? I keep mine around 85 degrees with 70% humidity and get great growth.

The tropicals love it and I bought it with fantasy football money which makes it sweeter. (to me)

 

[Carol 83]

and I dread the upcoming dance, back and forth. Only hitting 40s're yesterday and tonight, then going back to 60s for our lows, so they’ll go back out for about three weeks—I do baby them a bit.

I don't do the dance. Once they're in they're in. Once they're out they're out.

 

[bonsaichile]

I just put them in the ground, inder my bench

 

[Deep Sea Diver]

Here’s a link to a resources that shows multiple members methods of Overwintering Bonsai shown as case studies.

https://www.bonsainut.com/resources...ry-planning-and-case-studies-azalea-focus.49/

Cheers
DSD sends

 

[plant_dr]

My temperate trees all stay outside all year in a corner of my yard that is pretty protected from wind and weather. Pretty much everything I have is tough as nails so I don't worry too much about them.
I have a Ficus benjamina that comes into the dining room window and a lemon tree that hangs out in a storage room window just off the laundry room. There's no heat in there but an open doorway that lets the ambient air go through. It has done alright for years that way. No extra lights or doo-dads for me!

 

[yesimnathan]

Last year I overwintered my trees in my unheated garage. This year… I have many more trees lol. I’ll be adding some shelving in the coming weeks. Hopefully I can fit all my maples in there

 

[WNC Bonsai]

Most of mine go into a small greenhouse I put up a year ago last April. It is heated and set to stay between 34 and 36 degrees F. I do leave my larches, spruces, Austrian pine outdoors though. They can all take whatever Mother Nature throws at them.

 

[Jrmcmich]

Most of mine go into a small greenhouse I put up a year ago last April. It is heated and set to stay between 34 and 36 degrees F. I do leave my larches, spruces, Austrian pine outdoors though. They can all take whatever Mother Nature throws at them.

View attachment 613432

Have you monitored temperatures in there last winter? I wouldnt mind a greenhouse for winter but do worry about heating up some

 

[Leo in N E Illinois]

I live in zone 5b or cold side of 6a, depending on climate change. Seems to be getting warmer every winter. All my trees that are hardy to zone 4 or 5a, I simply set them on the ground. This includes most of the locally native species. So Black Hills Spruce, Boxwood (B. sempervirens), bur oak, elms, JWP, Jack Pine, Thuja, and others all just set on the ground.

Trees from milder climates go into an unheated well house. This is an underground feature unique to homes over 100 years old, or to homes not connected to municipal water supplies. It stays above freezing even in the coldest winters.

 

[Paradox]

Coldframe built along the north side of my house

 

[Kodama]

5b/6a over here as well. On the ground of pea gravel with thick layers of Pine needles as mulch and protected from wind. Deciduous only in attached unheated garage and tropicals on life support inside. I'll check moisture of pots periodically through winter and hope for snow as I also nervously notice more warming trends through winter.

 

[cmu268]

Mine just go on the ground and get mulched in. I put them behind a raised garden bed that offers a bit of protection from wind.

 

[Port Farmer]

More of a year round setup for me due to apartment living, tropical and succulent pre bonsai. Mostly AC Infinity growing Ecosystem using their AI controller. VPD target between 1-1.3.

 

[WNC Bonsai]

Have you monitored temperatures in there last winter? I wouldnt mind a greenhouse for winter but do worry about heating up some

I’ll have a post soon on heating a small greenhouse with photos, thermographs, etc.

 

[Potawatomi13]

Except for tropicals all stay on benches as the rest of the year. However if there is ice or snow some taller thinner ones go under the bench to prevent breakage.