
I'm worried, will my Juniper Bonsai be ok tonight?
I've had a Juniper bonsai since September and I'm well aware that the plant needs a dormant period and cannot be kept as an indoor plant, so I've been keeping it on an unheated, very sunny porch that is protected from the winds. The bonsai has been doing quite well these past weeks with about 20 F temps at night, but these next few nights it is supposed to be 0 F. The porch will probly be a few degrees warmer than the outside temps but not by much. My bonsai is in a ceramic container with bonsai soil, with moss on top of the soil. The container has drainage holes and sits in a larger container the has rocks in it. I fill that outer container with water so the bonsai can draw up that water when it needs to. Lately that water in the outer container has been freezing solid. I have wraped a large towel around the container, but I am still very concerned that these temps are gonna kill my bonsai. But I definetly am hesitant about messing up its dormancy cycle by bringing it inside.
Any suggestions?

- Gnome
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Vesper,
I've have kept my Juniper outside at similar temperatures (0F) and it did just fine. But there were substantial differences in my technique compared to what you describe.
First, the water in the outer vessel is worrisome to me. Your tree should not be sitting in water like that. Next my tree sits on the ground, mulched in up to the lower branches. When snow comes I allow, even encourage, a snow cover to serve as insulation. The earth has a lot of heat even though it may not seem like it and the tree seems content to over winter with no further attention.
Some changes I would suggest would be empty the outer pot of water and fill it instead with some sort of insulating material. Don't worry about the foliage but the roots will benefit from some protection. You could also move the pot next to the wall of your home which should help moderate the temperatures a little.
Both pots, or just the inner one, could also be put inside a cooler with some form of insulation around the inner pot/s.
Norm
I've have kept my Juniper outside at similar temperatures (0F) and it did just fine. But there were substantial differences in my technique compared to what you describe.
First, the water in the outer vessel is worrisome to me. Your tree should not be sitting in water like that. Next my tree sits on the ground, mulched in up to the lower branches. When snow comes I allow, even encourage, a snow cover to serve as insulation. The earth has a lot of heat even though it may not seem like it and the tree seems content to over winter with no further attention.
Some changes I would suggest would be empty the outer pot of water and fill it instead with some sort of insulating material. Don't worry about the foliage but the roots will benefit from some protection. You could also move the pot next to the wall of your home which should help moderate the temperatures a little.
Both pots, or just the inner one, could also be put inside a cooler with some form of insulation around the inner pot/s.
Norm
I would take the container with the water away from the Juniper. It really needs far less water than you think in dormancy. When it snows put a little snow on the top of it's soil and when it warms up it will melt and water naturally. But just damp soil is fine when they are dormant. I would worry more about ice in than soil freezing and damaging your tree's root system.
You could throw a couple of extra blankets around the pot to insulate it more but I agree that it will probably be OK even with the colder weather.
You could throw a couple of extra blankets around the pot to insulate it more but I agree that it will probably be OK even with the colder weather.
Last edited by djlen on Sun Jan 10, 2010 12:39 am, edited 1 time in total.
Ok, here's a pic of my bonsai from a few months ago, it still has this setup.
https://www.flickr.com/photos/17398687@N02/4045303298/
That lower brown container is the one with the water that is freezing. From what you guys have said, I think I'll remove that container and wrap the towel around the blue container.
https://www.flickr.com/photos/17398687@N02/4045303298/
That lower brown container is the one with the water that is freezing. From what you guys have said, I think I'll remove that container and wrap the towel around the blue container.
Hi guys,
I have a simular situation but my temps are not 0F they are only 25F-30F anyways the soil in the pot has completely froze, probaly cause it rained but I was woundering what to do....
My mom suggested putting it in the sun for a lil more warmth to help defrost it because tomorrow is the last day of the freeze any suggestions will be appretiated THX GUYS.....
I have a simular situation but my temps are not 0F they are only 25F-30F anyways the soil in the pot has completely froze, probaly cause it rained but I was woundering what to do....
My mom suggested putting it in the sun for a lil more warmth to help defrost it because tomorrow is the last day of the freeze any suggestions will be appretiated THX GUYS.....
Guys,
A Juniper is an amazingly tough and adaptable plant. Having said that we try to do the best we can to make it as easy and comfortable for them to over-winter.
I think both of your trees will probably make it through this current cold snap that many of us are experiencing and come back strong in the spring.
The fact of the matter is that most trees need so much less watering in when in dormancy that it is not necessary for drip trays or anything under them that would abet ice formations in or under them.
Vesper, I would remove the tray under yours if it was mine. It's not necessary at this time. During the coldest times I would move it close to the house on the porch where it would probably be a few degrees warmer than away from the house. Every little bit helps.
Keep an eye on your pots to check for ice/frozen soil within expending and breaking the them. This can happen in extreme cold and could potentially expose roots to the elements.[/url]
A Juniper is an amazingly tough and adaptable plant. Having said that we try to do the best we can to make it as easy and comfortable for them to over-winter.
I think both of your trees will probably make it through this current cold snap that many of us are experiencing and come back strong in the spring.
The fact of the matter is that most trees need so much less watering in when in dormancy that it is not necessary for drip trays or anything under them that would abet ice formations in or under them.
Vesper, I would remove the tray under yours if it was mine. It's not necessary at this time. During the coldest times I would move it close to the house on the porch where it would probably be a few degrees warmer than away from the house. Every little bit helps.
Keep an eye on your pots to check for ice/frozen soil within expending and breaking the them. This can happen in extreme cold and could potentially expose roots to the elements.[/url]
hey guys,
thx for the reply len oh I haven't watered it since the freeze started because I took into consideration that they don't need alot of water in winter bcause of dormancy so I haven't watered it in awhile and it looks gd still I was just worried about it being frozen
anyways thx for the reply
thx for the reply len oh I haven't watered it since the freeze started because I took into consideration that they don't need alot of water in winter bcause of dormancy so I haven't watered it in awhile and it looks gd still I was just worried about it being frozen

anyways thx for the reply
Thanks guys, I took the bottom cantainer away. I moved the bonsai a bit closer to the house, but I cannot place it right up next to the wall of the house because there is no direct sunlight there. I also wrapped a thick towel very tightly around the container. I checked the soil under the moss and it appears to be frozen, which really worries me, but I guess there isn't much more I can do but hope it survives.
- Gnome
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- Joined: Wed Jul 05, 2006 12:17 am
- Location: Western PA USDA Zone 6A
Vesper,
Just because the water in the soil is frozen does not mean that the plant itself is frozen. My pots stay frozen for extended periods during the winter. Evergreens do not need nearly as much light while temperatures are low so any spot on your porch should be OK. Here is some reading to help you make the proper choices.
https://www.evergreengardenworks.com/overwint.htm
I still have some concerns about leaving such a small pot exposed to very low air temperatures. A little extra precaution can do no harm.
Norm
Just because the water in the soil is frozen does not mean that the plant itself is frozen. My pots stay frozen for extended periods during the winter. Evergreens do not need nearly as much light while temperatures are low so any spot on your porch should be OK. Here is some reading to help you make the proper choices.
https://www.evergreengardenworks.com/overwint.htm
I still have some concerns about leaving such a small pot exposed to very low air temperatures. A little extra precaution can do no harm.
Norm
This is important for you to hear Vesper.Gnome wrote:Vesper,
Evergreens do not need nearly as much light while temperatures are low so any spot on your porch should be OK.
Norm
A few days......heck, even a week without direct sun will not harm the tree and the warmth of the house has the potential to help a great deal while the temperature is extreme.
Wrap the pot in blankets and put it over against the wall of the house. I have two thermometers outside my back door. One is out away from the the house a bit and the other is right up against it. The one against the house is regularly 2° - 4° warmer.
- Gnome
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- Posts: 5122
- Joined: Wed Jul 05, 2006 12:17 am
- Location: Western PA USDA Zone 6A
Vesper & GardenerX,
Here is a shot of some of my temperate plants today.
[url=https://img685.imageshack.us/I/winterf.jpg/][img]https://img685.imageshack.us/img685/6770/winterf.th.jpg[/img][/url]
So far my low temperature has been 1F and I have seen it go lower in the past. Of course the roots don't get that cold. These trees benefit from being on the ground where heat from the earth is trapped under a thick layer of mulch and snow. I leave them like this with no attention until spring. The only time I have lost anything was due to my own foolishness. An air layer with tender new roots did not make it one year, that sort of thing.
Other plants are stored in an unheated garage. I have some fairly young Pines that are inside and the only light they receive is from a few windows and a double tube fluorescent ceiling fixture. As we have mentioned that evergreens do not need nearly as much light at low temperatures. In fact there is some evidence that bright light at low temperatures can actually cause damage.
https://www.evergreengardenworks.com/dormever.htm
Norm
Here is a shot of some of my temperate plants today.
[url=https://img685.imageshack.us/I/winterf.jpg/][img]https://img685.imageshack.us/img685/6770/winterf.th.jpg[/img][/url]
So far my low temperature has been 1F and I have seen it go lower in the past. Of course the roots don't get that cold. These trees benefit from being on the ground where heat from the earth is trapped under a thick layer of mulch and snow. I leave them like this with no attention until spring. The only time I have lost anything was due to my own foolishness. An air layer with tender new roots did not make it one year, that sort of thing.
Other plants are stored in an unheated garage. I have some fairly young Pines that are inside and the only light they receive is from a few windows and a double tube fluorescent ceiling fixture. As we have mentioned that evergreens do not need nearly as much light at low temperatures. In fact there is some evidence that bright light at low temperatures can actually cause damage.
https://www.evergreengardenworks.com/dormever.htm
Norm
You guys have been SO much help, thank you. I put the bonsai as close to the wall of the house as possible. I checked the soil again and even though its still very cold out, the soil has thawed a lot from what it was like this morning, because my porch is so sunny. I feel very confident that my bonsai will be okay now, thanks again!