PC404 wrote:

Hello, welcome to the magical world of bonsai (also known as, oh my god, are my trees dead every time I leave for the day club).
I'm not an expert but have been in the hobby for over a year now. I've only bought two nursery stock and grown the rest from seed, but from my experience, I would wait to repot for a couple weeks.
In this time, observe your trees, and make sure they are acclimating well to their new environment. If after about two weeks they are still doing well, you may change the soil into something more professional or repot entirely. I recommend the beginner's course lecture for good, professional information on how to do this. It's reasonably priced as well .
As for whether you should keep them outside, remember that plants can get temperature shock easily. Try to recall the temperature of the place you bought them and keep them around that level for now. I assume you are in the Western Hemisphere. Once spring rolls around and the weather is warmer and milder, transition them to your balcony and arrange them to how much sun exposure they need. Let them adjust to the shifting temperatures outside.
When the cold season rolls around again next year, you want to protect your little trees while still keeping them on their schedule. I live in South Texas, and our temperature swings are so violent that I just keep my trees in a small, separate building (the temperature can change 50 degrees in the course of a day) but I have seen people plant their trees in the ground or planting beds for the winter, so they are insulated by the soil. Setting up a sort of tent to block the wind with a bedsheet is a good tactic. And I suspect a weak heat lamp would help as well. During the winter, I recommend setting up a grow light for your trees to ensure they get their sun. You can also bring them inside for winter as long as your home is not too warm that they will think it is springtime (That happened to my lemon tree. It bloomed and now it's growing tiny lemons in the middle of the winter ). If you bring them inside, make sure they are by a well-lit window or grow light.
And finally, I recommend doing some reading into the physiology of trees and plants in general. When you know how a tree works and what it needs to thrive, it is a lot easier to use discernment to solve issues like this.
Those are two cute little trees! Best of luck! 

Thank you for your recommendations. I thought about it and, perhaps these two trees could have spent their supposed dormancy period in the shop without being dormant at all, where it's slightly warm. Yet, a lot of people recommend keeping them outside, nevertheless it is a risk that tree roots may not adapt to this sudden environment change especially in cold weather of Toronto, Canada right now. Though, I took that risk with a little bit of protection that I could google, observe and thought of. 

I have a mini greenhouse setup, but it's basically unheated, protecting the trees from wind, and frost if possible. I'm using foil isolation for the ground part which is my balcony can be a little cold from the surface. I put them in a shallow transparent storage box, with fir bark mulch filled around the pots and some on the soil to create some more insulation from the cold weather if possible. I thought about heating the greenhouse with a device to adjust slightly to 5 C degrees but that's an expensive method. 

I'd try to keep the trees outside as much as possible, nevertheless the outcome will be decided in the following weeks. I realized I shouldn't buy the trees in the winter in the first place because it's not a good time to keep them alive as a beginner.

I would feel sad if they die, although it's okay to make mistakes so you can learn from it. There's a lot of information available online, which are good solid and others based on personal experiences which can be true based on their environment. I took a chance and perhaps gambled but let's see.

Thank you for your time sharing your experiences.

I am just a beginner in bonsai. 8 years of experience in the hobby and 7 with junipers.

I live in western Sweden close to the ocean. Similar to usda zone 7 but a lot wetter in winter. A mild area of Sweden and very mild compared to Toronto. I do not need to protect my trees from the cold, but I think protection from excess rain is beneficial. So I keep them in my unheated greenhouse in winter. The worst cold spell they have gone throe is 6 weeks of below minus 10 day and night. Lowest recorded temperature during that period was -18. And they did great.

In late winter when the sun starts to go higher on the sky it heats up very fast in the greenhouse early in the days. I open the doors fully every sunny day to get the heat out and prolong the dormancy. Junipers and pines are the first trees to move out of the greenhouse sometime in march usually.

However, in the forests around me junipers is growing on thin soil and with shallow roots without anyone pampering them. The chines ones like yours grow good in gardens around me as well. So my pampering with the trees may not be necessary.

The trees on the pictures has not yet broken dormancy. I think keeping them outdoors at all times is not a problem. Toronto gets a lot of snow to my understanding. Is that right? In that case I would recomend to cover the tree in snow on the coldest days. Snow is a great insulation.

Nigel Saunders from the youtube channel "the bonsai zone" is in the Toronto area and active in the Toronto bonsai club. Watch his videos and join the club. That is my best advice.

Tropfrog wrote:

I am just a beginner in bonsai. 8 years of experience in the hobby and 7 with junipers.

I live in western Sweden close to the ocean. Similar to usda zone 7 but a lot wetter in winter. A mild area of Sweden and very mild compared to Toronto. I do not need to protect my trees from the cold, but I think protection from excess rain is beneficial. So I keep them in my unheated greenhouse in winter. The worst cold spell they have gone throe is 6 weeks of below minus 10 day and night. Lowest recorded temperature during that period was -18. And they did great.

In late winter when the sun starts to go higher on the sky it heats up very fast in the greenhouse early in the days. I open the doors fully every sunny day to get the heat out and prolong the dormancy. Junipers and pines are the first trees to move out of the greenhouse sometime in march usually.

However, in the forests around me junipers is growing on thin soil and with shallow roots without anyone pampering them. The chines ones like yours grow good in gardens around me as well. So my pampering with the trees may not be necessary.

The trees on the pictures has not yet broken dormancy. I think keeping them outdoors at all times is not a problem. Toronto gets a lot of snow to my understanding. Is that right? In that case I would recomend to cover the tree in snow on the coldest days. Snow is a great insulation.

Nigel Saunders from the youtube channel "the bonsai zone" is in the Toronto area and active in the Toronto bonsai club. Watch his videos and join the club. That is my best advice.

Thank you so much. I'll search his channel and maybe even contact him. 
Toronto usually get less snow, at least in the downtown area, and it is very dry lately in terms of precipitation. On the forecast it generally says 0-2 cm of snow, when it's snowy and hardly ever see some snow or gets melted quickly. If it was the opposite I also though about gathering some snow and putting it onto the trees and soil to further insulate.

In the late winter I expect to see higher day temperatures here, so I'd probably apply the same what you do with the greenhouse.


 

Topfrog calls himself a beginner after 8 years. I got my first tree in 1969, and I still think of myself as a beginner. 

Trees  belong in the environment that is as close as possible to where they evolved. In Toronto a birch or larch has to be outside. They evolved in that kind of winter. Ficus would have to be inside because they evolved without cold winters. Unfortunately they also evolved without central heat and low humidity, so the right environment is hard to supply. 

Junipers evolved in many environments so the exact environment yours needs is hard to tell. Stores rarely include exact Latin names so it is hard to know how cold yours need winter to be.

In many  cases I think "it will do fine indoors" really means "it will live until the check clears". 

Your best bet is to find a local club and get their advice. They know the local climate well and someone might be able to recognize details of your juniper. 

Well. This is a cultivar of  juniper procumbens, it is called nana. The natural distribution is Korea and japan. It is rated as hardy in usda zone 4-9, which is quite a broar range. Normally it makes sense to add one zone for trees grown in shallow pots. So 5-9 in a pot.

Toronto is in zone 6.

Texas is big. It covers zone 6-10. I would guess population places in south Texas is not within the range.