Overwintering Zone 6

It's hard to think of freezing temperatures this time of year, but I have a couple of questions about overwintering my bonsai trees.

This will be my first winter with my trees. I have a couple of Chinese Elm, and a couple of Azaleas. I live in Zone 6 and winter temperatures can get sub zero here. I have also seen 70 degree Christmases. Snow fall is usually sparse.

Should I bring my trees into my unheated garage? If so, how much light do you recommend? What kind of watering regimen do you recommend?

OR

Should I leave my trees outside on my covered porch? If so, should I do anything special to the pots such as wrap them in burlap?

Thanks in advance for any and all advice on this topic. I look forward to reading your responses.

Dave.

Dave--I live in Kentucky, too (Murray, in the far western part of the state). I lost a number of trees when first beginning (well, ALL of the first ones, really). This was as much due to poor soil mixtures as anything, but winter played a part, too.

Assuming we are talking about hardy trees, not tropicals or particularly cold-sensitive species, everything is wintered outside. (As examples of trees I do not leave outside, there is citrus, culinary bay leaf tree, oleanders, etc. These are mostly not bonsai.)

Everything else is wintered outside with varying degrees of protection. Some hardy, deciduous trees, particularly larger, but somewhat sensitive trees, I keep in an unheated storage shed. The lack of light during the hardest part of winter does not seem to bother them.

Others, those in smaller pots, or somewhat freeze-sensitive, such as ginkgo, I place in a small cold greenhouse (about 4" X 5" at the base) that is in a shaded, protected location next to our home. I usually pack some straw around the pots for some minor insulation.

Everything else goes in the low pathways between the raised beds of my vegetable garden. This gives a little protection from the wind. The pots and lower portions of the trees are mulched with straw, and I make sure they don't sit in standing water during wet weather. I usually place straw or concrete stepstones under the pots to ensure this. This pathway area is also lined with landscaping fabric to keep soil from entering the drain holes of the pots. My chinese elm is in this category. I would expect also an azalea would be, too, depending upon the species. They might need a little more protection.

With this routine, I haven't lost anything to winter cold in years, although I have seen some root damage that is probably as much due to excessive wetness as to the cold. These trees have always come back, but I am using a freer-draining soil mix this year.

By the way, if you don't mind saying, where in Kentucky do you live? You may PM me if you prefer.
Oliver

Yeah I pretty much do the same thing here in Louisville except I don't have a green house so I improvise one. THe trees and kusamono go under the benches (which takes some rearranging of the benches usually) sitting on something to get them off of the ground (which I think also allows for air space under the posts to help keep them insulated from the frozen ground) mulch them in (I just use larger hardwood mulch but I like the straw idea) and then I throw some plastic over the whole thing. The top is completely blocked from light by the wood from the benches so the temperature wont rise and the only other thing I do about once a month is if it snows I will open it up and throw a little snow on top of everything so as it melts it keeps thing watered. I haven't lost anything (at least in the winter) doing it this way. Good luck, I would be interested in knowing where abouts you are too.

I live in Lexington, KY.

This excellent article has answered many of my questions as to the why and how of overwintering.

http://www.evergreengardenworks.com/frzekill.htm