To quote a friend on the forums, do you plan on keeping it inside every winter for the rest of it's century long life ?
Otherwise, plant it outside...it's not a baby after all.

dbarron, I do not understand your response. Are you saying to remove it from the pot and plant in the ground? I would keep it inside, but I thought it needed dormancy.

That's the trouble with stores that sell trees they have no knowledge of (was it a big box store?) and your tree might be ok in NY, but it will need real protection such as a container definitely larger than its pot, with lots of mulch between the pot and container, plus some on top. And if you can keep it in that open garage it'll at least be protected from serious wind. Most important would be to make sure it's watered the day before a hard frost is predicted... but... all that being said, is there no place inside where you live, like a back room, etc., that you can keep relatively unheated over the winter, but still provide good light, and leave the tree there through March, watering less often than you otherwise would from Dec. onward?

Actually, I bought it from a large greenhouse that specialized in Bonsai, but the owner wasn't all that interested in educating me. He did tell me it needed dormancy but not how to do it safely. I have kept it inside the past 2 winters. Moochinka, your message gave me a great idea that hadn't occurred to me. When you asked about an unheated backroom I thought, "no, I don't have anything like that. But then I realized I do! I have an enclosed front porch on the north side of my house with all windows and a tiny enclosed back porch with one window. I don't know why I didn't think of this before. All I can say is "duh!" The small back porch would be cozier and get direct sunlight for a few hours. Should I still use a larger container filled with mulch? Thanks again.

Rochester, is there a peer group in your city....a bonsai club, perhaps? There's nothing like getting advice from those within your own community about how to maintain your bonsai. And shame on the bonsai seller for not being interested in educating his customers.

Hi - not knowing how cold overnight in Jan. your room gets, I can't say what to do re container or mulch - but your pot is really small, so it's something to consider at anything below 40 F, though a C. elm in the ground would be ok to around 20. Kind of your call I guess. Do let it go as dormant as possible however, back room with or without some protection (why not a low box with some mulching around the pot?) but not before November.

Moochinka, I am sure it will get very very cold on that back porch. It is unheated and has thin walls. However, it does share a wall with the side of my house, so that should give off a little heat. I haven't ever checked the temperature, but I imagine it can get to zero on a cold night. It will be easy to get at for watering in the winter, which is also good. I will put some mulch around it as you suggested, too. thank you.

If it gets to zero (do you mean 0 F. or 32 F?) then you definitely need it to be in a larger and mulched container up against the house wall. Good luck.

I mean if it goes much below freezing (32) then it needs good protection... zero F would be way too cold. Way.

This post was edited by moochinka on Mon, Oct 6, 14 at 15:01

I was not ready for the severity of last winter. had a few trees on my unenclosed porch semi protected. Lost a maple and a privet. i also thought i lost the elm. It did not bud out in the spring. I removed it from the pot and planted it in the ground and sure enough it sprouted from the trunk. Unfortunately all the old branches with nice ramification i had worked on died. I'm guessing the roots can survive when it is very cold however the small branching may not.
I am a little confused----Why would you have to ' provide the tree good light' if it is dormant. I am assuming if you leave the tree outside until November all the leaves will fall. Is light still needed if there are no leaves to photosynthesise?
Or are we saying that Ulmus parvifolia( I believe the tree we are referring too) is not deciduous and retains its leaves in dormancy.
This point has always confused me with this tree.
Any insight?

Hi - you're right about no leaves of course, but I was thinking that at some point (Feb/March, depending on where you live) that some sun would be needed to awaken things, especially if the tree was in that close-to-but-not-frozen environment. Sun is what gets buds going after all, and then the rest of the tree comes out of dormancy. Funnily enough, however, C. elm may well hang onto some leaves even when dormant, depending on the climate... just depends on the tree, the cold, the climate, etc. etc.

This post was edited by moochinka on Sat, Oct 18, 14 at 21:29

Have you done any research online? There are numerous bonsai website that discuss winter protection in depth. It is probably the number one concern of bonsai enthusiasts.

I don't do bonsai but I DO grow a lot of trees in containers and the principle is the same. Since the plant's roots are the most vulnerable to cold and trees in containers - bonsai or full size - do not have the benefit of the insulating soil mass around the root ball, some sort of other protection must be provided. And while still maintaining suitably cold temperatures for the plant to complete its necessary period of dormancy.

The pot-in-pot method mentioned above is one way, Storing in a greenhouse or cold frame where the temperature can be controlled is another. Also an unheated garage or porch or root cellar - light is not a concern during dormancy. Even burying the bonsai pot in the ground and mulching over and around it will work.

The temperature in the protected location needs to remain below 45F and above 25F. Often that can be achieved in an unheated attached garage - even though the temp outdoors drops considerably below, radiant heat from the house will often maintain the temp inside the garage at adequate levels. Be sure to monitor during extended cold spells with a thermometer. And wrapping the pot (and plant - leave top open) with bubble wrap is a great way to provided some added insulation.

The attached link is from a bonsai website with detailed winter care information. It's two pages of valuable info for any bonsai enthusiast.

Here is a link that might be useful: Bonsai winter care

Been doing bonsai x 40 yrs... but thanks anyhow.

You may well be experienced but the OP is not. It's an excellent website for the novice or the more experienced bonsai fan

Yes moochinka Ive noticed my Ulmus parvifolia hanging on to leaves during a more seasonably warm winter.First year I had it inside and it dropped a lot of leaves but not all. Of course last winter it dropped them all. Thats why I question its hardiness.We will see what happens this year.

Hey Gal Good article.I think we may have discussed this subject before on the maple forum. My concern is with this particular tree. Most come from nurseries where they have been overwintered in greenhouses most likely in Florida. I think they take a while to get adjusted to more northern climates.
Anyway I will be better prepared this winter. Before last winter our winters where mild.

Overwintering most temperate material is very easy in theory. How well you can apply that theory is the key to success.

Essentially, you want to keep your trees as cold as possible for as long as possible w/o root temperatures dropping more than a couple of degrees below freezing. Keep them in a place where temperatures are cold enough, and where the warm extremes (above 42* F) won't stimulate the plant to growth. Once growth is initiated by warm soil temps, the plant's ability to tolerate cold is diminished very significantly.

Whether or not CEs actually NEED a period of dormancy and how much chill they actually need is a genotypically inherited trait, so it will vary significantly from tree to tree. The best plants I've seen have all been grown in places where they get several months of cold rest before beginning the spring push, whether the rest is in an unheated garage, mulched in well on the N side of a heated building, or buried in the ground where temps allow.

Al

Hi,new to the site,got the whole winter garage thing,my only question is does this Chinese elm need light or not..thanks,Mark

If it's dormant - no.

If it's growing - yes.

A tree that's growing in the dark is essentially running on energy reserves, which are finite - same as the energy stored in a battery. Not only that, but it's highly unlikely you'd want to keep any of the growth that occurred under those low light conditions, so the tree will be 'paying' for growth you will likely remove.

Al

So would a grow light be needed at times?

If the tree is not dormant, is growing, and is not receiving enough light, then supplemental lighting would be a plus. If the tree or dormant or quiescent by virtue of low temps, no light or supplemental light is required. I have several friends that over-winter their trees in 6' deep pits lined with shelves and covered by a deck-like structure that eliminates all but some small vestige of available light.

Al

When I bought my Chinese Elm, I asked the online dealer from Chino Calif. what would be an easy indoor tree other than a Ficus; I have several varieties of Ficus and I wanted to expand. I wanted an easy tree. I'd spoken and worked with these people in the past. Chinese Elm is NOT an easy tree, as I found out when I started investigating its care. No one seems to agree on how to winter-over this tree in a temperate climate that occasionally can peak to the 70s in December (South Jersey) for a period, or even ANY temperate climate really. No one seems to know how long the tree needs to stay dormant, and there is a lot of disagreement.

What I've concluded is this: Chinese Elms, and most bonsai trees prefer to be outdoors in the summer. All bonsai trees are outdoor plants. When it gets cold, some will tolerate (and need to) be inside in a sunny window, but most require added lighting. The Chinese Elm, though advertised as an indoor evergreen tree on many sites might grow in a tropical climate as an evergreen, but if you do live in a temperate climate, be prepared for a challenge.

The clincher is that some Chinese Elms originate in the sub tropics and some originate in warmer temperate regions, and of course, we don't know which we get. I've come to the conclusion that Chinese Elm will tolerate being an indoor plant in the winter (but will drop its leaves either all at once or when it starts to bud out in the spring, sort of like a Pin Oak) but they prefer to go through an actual, winter-induced, cold dormancy period.

After reading this string, I've decided to do this: I will put my tree on a shelf in the window of my attached, unheated garage. I will sink its pot into a deeper mica pot surrounded by a bonsai mix with a wee bit of organic material. If the temperature is going to drop below 20 degrees Fahrenheit outside, I will have created a "cone of warmth" with bubble wrap (with an opening at the top. Thanks for the suggestion!), and I will keep a thermometer in the garage. I will water the tree once or twice a month if the temperature is above freezing. I will check it regularly and the minute it starts to bud out, I will bring it in and that will be its dormancy period. CHINESE ELMS ARE NOT EASY TREES. LOL.

Why this wonderful bonsai merchant in Chino Calif suggested the Chinese Elm and not, say, a Serissa or any other tropical, I don't know... except they don't sell Serissa.

Good luck, and let me know how it goes. I'll try to let you know how mine does.

Meadowmorph

Id there electricity in said garage? You could get FlexWatt a subfloor heat tape, or similar reptile heater to create a 40-45F area in the garage.

I live in MI and over-winter all my elms (at least 15, maybe as many as 20) in an attached but unheated garage, including U. parvifolia. I lost one elm a couple of years back because I missed a winter watering and it went dry, but that was a seiju elm. I find all elms very easy plant to grow, attributable to their high level of vigor.

If you have concerns about the temps getting too low, you can set your tree on the garage floor and cover it with an overturned cardboard box. When it gets really cold, it will be as much as 15* warmer in the box.

Al

Thanks, tapia. I'm beginning to think the internet is a curse as well as a blessing with conflicting information. I still am not sure if my Chinese elm is dropping leaves because it's going into dormancy or I'm keeping it too moist....or too dry. LOL. One expert says I should keep my Serissa on the moist side or on the dry side, the same with my Arulia. Michigan is a little colder than Southern New Jersey, but I'm going to follow your suggestions. I was going to put it on a shelf by a window, but I think the passive solar will bring the temp up too high. I'll keep it further from the window. I do know my Chinese Elm has stopped growing, using less water, and though the highs are mid 70s and the lows have been around 50, it could be going into dormancy. Once I get it through the first winter, I'm sure I'll not be quite so manic.

My three chinese elms spend their winters outside and they do a whole lot better there. Two of the pots will be buried in ground with some leaf mulch piled up. The third will spend time in an unattached shed with no heating. They are quite robust plants. In spring when buds break out I spray them with Bayer 3-in-1 once. I get this leaf curling aphid of some sort that can kill the leaves in no time. Since the leaves curl any other pesticide cannot get to them easily. My friend lost all his chinese elms to this pest.

And my elms are still green with no sign of leaf drop yet. One of them is still producing new light green leaves. Probably it is the confused one.

I find Serissa to be a fairly easy plant - not temperamental as a lot of internet info seems to suggest. The only time I have killed them is by letting them go too dry. It is a common hedge plant in India since goats and cows avoid it due to its incredibly foul smell. But it survives 100+F with no problems. Apparently it is a zone 7 plant too. I should try and keep one of my plants outside in the shed this year. I have too many of those since they root so easily.