Is this adequate for winter protection?

[Tntthunder]

So I am preparing for my first winter with my first few trees. I live in an apartment with a balcony and can't bury my pots so I have been trying to think of ways to protect my trees.

I live in Finland and it can easily reach -25 Celcius in my location. What I was thinking was burying my pots in a storage box (like in the picture) using mulch, Styrofoam, straw, or burlap to insulate the box and pots. Also pile up snow on the outside of the box to protect it even more.

I was then planning to find a material to cover the top of my trees on particularly windy or cold nights to protect from frost. Any suggestions on materials? I have read fleece works in areas with - 10 but haven't been able to find it for anything colder. Would this be adequate?

My trees are a few Chinese Junipers, and a couple mugo Pines.
Any advice would be great.

 

[rockm]

This offers no protection whatsoever. You cannot conserve heat that isn't there. There is no ambient heat source, as with mulching on the ground or storing in a sheltered location. This container will flux in temp just as the air does, regardless of the insulation.

 

[FreshAirSunshine]

I’d not say there’s *no* heat source - it’s black so it’ll absorb heat from the sun relative to white snow around it, but it’s going to be quite minimal. The result will probably be the same as no heat.

 

[Wires_Guy_wires]

Finland has some harsh winters my friend.
If you're going to use a box like that, you should set it against your house walls on the outside. The snow might provide some insulation and it might stay warm enough to not completely kill the plants. But.. The hard part is that the box will be buried under snow. And if temperatures reach 0 degrees C or higher, you're going to have to water your plants at some point. How would you know what the temperatures are?
That's a whole new set of challenges that I don't know about.

A totally closed off box isn't my preference. You want air to get in and out, otherwise the plants will suffocate. Maybe some Canadians or Alaskans can chime in?
@Canada Bonsai maybe?

 

[Tntthunder]

Finland has some harsh winters my friend.
If you're going to use a box like that, you should set it against your house walls on the outside. The snow might provide some insulation and it might stay warm enough to not completely kill the plants. But.. The hard part is that the box will be buried under snow. And if temperatures reach 0 degrees C or higher, you're going to have to water your plants at some point. How would you know what the temperatures are?
That's a whole new set of challenges that I don't know about.

A totally closed off box isn't my preference. You want air to get in and out, otherwise the plants will suffocate. Maybe some Canadians or Alaskans can chime in?
@Canada Bonsai maybe?

Oh I wasn't going to close it off. I planned to just bury the pots in it with mulch/soil or something.kind of like a garden bed, just on a balcony or something.

The lid would be off and the trees themselves being outside. Was thinking of using burlap or something to cover them on day with strong wind and such. I was more thinking of this being a way to insulate the roots a bit from harsh winds and such as the Junipers and and pines seem to be hardy enough for my zone. Google says they about zone 3-8 I am zone 5b.

 

[Paradox]

If any of them, the mugos have the best chance of surviving.
I agree with the advice above. Snow is your best friend as far as insulation

 

[Brim Gribley]

Would anybody know if A large cooler might work? I have no experience in keeping trees alive in that cold of a winter, I’m wondering if It would have a little insulation from extreme temperature changes.

 

[Paradox]

Would anybody know if A large cooler might work? I have no experience in keeping trees alive in that cold of a winter, I’m wondering if It would have a little insulation from extreme temperature changes.

The problem is without a source of warmth, the inside of the cooler will get as cold as the outside at some point.
Coolers are insulated but the ice inside keeps it cold. The insulation just slows down the melting.
Eventually it melts anyway and gets warm unless you add more ice

 

[Tntthunder]

Would anybody know if A large cooler might work? I have no experience in keeping trees alive in that cold of a winter, I’m wondering if It would have a little insulation from extreme temperature changes.

One of the things I have heard in my searching of solutions was a styrofoam cooler box. This was mentioned by a guy with -15 temps. So maybe that would be a better way to go for me.

 

[sorce]

If nothing is too expensive, I'd leave em all out and see what happens.
What's likely to happen is a realization they are fine and this may be over thought.

Sorce

 

[BobbyLane]

If nothing is too expensive, I'd leave em all out and see what happens.
What's likely to happen is a realization they are fine and this may be over thought.

Sorce

thats probably what the nurseries and garden centres do in Finland. OP should contact a few and ask them what they do.
because on a balcony the plants will be less exposed to the elements and benefit from heat emitted in close proximity from his building.
trees placed up against the balcony wall, against the building windows and under a bench or table should be fine.

 

[ShimpakuBonsai]

If you google hardiness zone for pinus mugo and chinese juniper it says roughly zone 3-7 and zone 4-9.

If you are in zone 5b the trees should be able to handle the temperatures.

 

[BobbyLane]

This was my set up, privacy screening also works as a windbreaker, plus its a roofed balcony. you didnt mention if yours is roofed or walled at the sides and that makes a HUGE difference.
trees like taxus i would place on the floor underneath tables n benches over winter, up underneath the window you see here, everything else is as tough as nails, our winters arent as harsh tho, but i only use mainly native species anyway, your native trees would be similar to ours.
spruce and the like would be fine outside, along with beech, hornbeam etc and scots pine etc

 

[Tntthunder]

This was my set up, privacy screening also works as a windbreaker, plus its a roofed balcony. you didnt mention if yours is roofed or walled at the sides and that makes a HUGE difference.
trees like taxus i would place on the floor underneath tables n benches over winter, up underneath the window you see here, everything else is as tough as nails, our winters arent as harsh tho, but i only use mainly native species anyway, your native trees would be similar to ours.
spruce and the like would be fine outside, along with beech, hornbeam etc and scots pine etc

Sadly nothing like that for me, have a very open balcony with only other balconies as a "roof". Hopefully next summer will be moving to a place with a bigger glassed off balcony so won't be much of an issue.

In the picture you can see the balcony from my dirty door, and across the way see examples of the other apartments with the same balcony.

It also gets pretty windy through the buildings, so my main thought process was largely to try and protect my trees from the freezing winds and such, they're currently all huddled together by the little window.

 

[Tntthunder]

This was my set up, privacy screening also works as a windbreaker, plus its a roofed balcony. you didnt mention if yours is roofed or walled at the sides and that makes a HUGE difference.
trees like taxus i would place on the floor underneath tables n benches over winter, up underneath the window you see here, everything else is as tough as nails, our winters arent as harsh tho, but i only use mainly native species anyway, your native trees would be similar to ours.
spruce and the like would be fine outside, along with beech, hornbeam etc and scots pine etc

For some reason my original comment didn't include the picture.

 

[BobbyLane]

my roof is the floor from aboves balcony. the screening on one side i put up myself. you could line yours with bamboo i guess, some people do that for privacy. also provides some wind protection.

 

[rockm]

For some reason my original comment didn't include the picture.

Your balcony is much like a roadway bridge on the highway- It is exposed on top, bottom and three sides to the air-it will freeze and thaw according to air temperatures. Using a container to protect against that is pretty futile, since the container won't have any kind of ambient heat to conserve. It will also isolate the pot from the ambient heat that comes from the exterior wall.

From the looks of how the balconies are set up, they are exposed on all but one side to temperature--much like a roadway bridge, the balcony will freeze as the air temperature drops. You best source of protection is the building's exterior wall on the balcony. If this were my location, I'd place the trees and pots on the balcony's surface as close to the exterior wall as possible and cover the pots with mulch--up and over the pot top surface as deeply as possible.

The mulch will help trap and lag some of the heat that will radiate (slightly) from the wall as it is heated on the interior and has more mass to sustain it--it will remain relatively warmer than the air...FWIW, don't confuse what "warmth" the trees need with what humans need. Your trees don't need to stay "warm" by human standards.

 

[hemmy]

I’m a winter newbie also. What about an electric heat source for the periods when the temperature is below -6C (~21F) for long periods? Outdoor heat mat or soil cables? That combined with putting rigid, sheet foam insulation against the railings of the exposed balcony to block the wind?

 

[penumbra]

I remember several years ago I had a large group of clivia in one of those cheap plastic portable greenhouses over a cold late spring night. Every leaf that was touching the plastic was destroyed. The plants themselves did fine as did the leaves not touching the plastic.
Interpret this as you will.

 

[dbonsaiw]

There's a huge difference between a heat source and insultation material. With insulation, the temperatures inside the box will ultimately reach the same temperatures as outside. It will happen somewhat slower as the box is insulated. The same will happen the other way, with thawing happening slower as the box is insulated. Insulation is good in the fight against a constant freeze/thaw cycle and helps keep the frozen trees frozen until spring has officially sprung (or as close as possible). If temps are simply too clod for your tree to survive, insultation will not save it.

Keeping trees on the ground allows the tree to benefit from the heat being generated within the earth. Mulch them in and you have the added benefit of the insulation keeping the core of the mulch pile higher than it would otherwise be.

Adding additional external heat sources will complicate the issues, IMO. At the very least, you will need a way to monitor the temps of your trees and be able to adjust the heating accordingly. Can't be too hot or the trees will wake up. Then if the trees are in an enclosure with external heating, you need to consider humidity levels and air flow.