Working on trees during the winter?

[jpaulhamus]

I have another question for everyone about a subject I've not heard much about: working on your bonsai trees during the winter months. Temperate trees, not tropicals. Basically I'm wondering what can and can't be done to your trees during the winter. For example I know a lot of people wire and prune their deciduous trees during the winter while they are bare since it's the best time to see the branch structure. A lot of people wire their conifers during the winter. Just wondering what else people do to their trees during the winter, like pruning. I usually find some nice trees for great clearance prices at the end of the season at local gardening places and would like to fiddle with them some over the winter but I'm always afraid to and wait until spring. Could you style a tree during the winter, doing heavy pruning and all? If I wanted to cut off a major branch I would probably cut it off and leave a stump and then use concave cutters and make a flush cut with the trunk in the spring so it heals better. Are there certain species that should or should not be worked on during the winter? Of course any repotting would wait until spring. Just wondering, like I said I haven't heard much discussion about this. Thanks!

[centaura]

I will do light trimming and wiring in the wintertime, though avoid hard pruning. Your idea of pruning to a stub and then coming back in the spring would probably work, though in my mind that just means I've had to cut it twice. I always seal any cut that I make in the wintertime, as the tree's natural sealing mechanisms are dormant and unsealed wounds would dry out deeper into the tree than a spring or summer cut.

-Cat

[jpaulhamus]

Hey Cat, thanks for the response. Yeah my initial gut instinct is to do major pruning during the growing season so the tree heals faster not while the tree is dormant and resting. I've seen stuff in books though where they are doing a major styling I'm guessing late winter. For instance in Harry Tomlinson's The Complete Book of Bonsai they show him styling a Cotoneaster while it is bare. He does everything (pulls it from the nursery pot, prunes it hard to style it, and pots it up) and then they show it leafed out a few months later. Like I said I'm guessing this was late in the winter and I'm sure he kept the tree in somewhere so it was protected after the styling, but in any case the tree looked dormant to me. Stuff like that makes me wonder what all people have done with trees during the winter months.

[ross.clark]

Once buds begin swelling in late winter is a good time to prune back twigs to one or two nodes. Earlier in the winter it is not so obvious which buds are destined to break.

[jpaulhamus]

Thanks Ross, that sounds like good advice. Jason

[shipsquartersfarm]

I do most anything, especially to conifers, in the winter. Major pruning, especially on Japanese maples, is supposed to be increasingly avoided as spring approaches, but, in my hands, they bleed quite a bit at any time of the year. I do not do much repotting until very near spring, but I know people locally (Maryland) who do, successfully. They do protect the trees afterwards.

[jpaulhamus]

Thanks for the info. It's neat to hear you are doing extensive work on your trees during the winter months. I know it goes against what most people would think they should do. Neat to hear about the repotting as well. The one guy I talk to locally repots most of his stuff in February, then by the time warmer weather comes around here (sometimes late March but usually sometime in April) his trees have recovered and are good to go and he doesn't have to worry about them being out. I winter my trees over in my unheated garage (like he does) and some of my stuff was starting to bud out in February last year so they got potted, but last winter was unseasonably warm. I had a tough time keeping my garage below 40, so stuff moved earlier. This year is a different story and my garage is still in the low to mid 30's so it will be a while yet. Thanks again, interesting stuff. Jason

[sbutler]

Thanks for the advice on repotting. It seems early, but, the buds on some of my elms are already starting to open. My garage is unheated but this winter has been mild. I'll repot them this weekend then. Question, once they start leafing out (probably in the next week or so), should I move them outside?

Steve
Zone 7a

[jpaulhamus]

Hey Steve, yeah wintering stuff over in an unheated garage really changes things. Temps stay way more consistent and it usually warms up enough that things start budding way before they would outside. So things move faster indoors then you kind of have to wait until things catch up outside. None of my stuff is doing anything yet, but it's been cold here. My garage is still in the low to mid 30's. Last year at this time it was in the low to mid 40's even pushing 50 at times in there and stuff was budding. You don't want to move things out too soon, especially if it's still cold and especially after potting them. I usually wait a month to put them out unless temps are staying above freezing. I have quite a few trees to move so I want to do it all at once and not be moving stuff back and forth. For your elms I would wait until the leaves harden off before you put them outside. If they are still soft when you put them out they can really get damaged by frost and they tend to get a bug. Not sure what it's called but if you see your leaves all curled up in a roll there probably is a bug inside. So wait until the leaves are fully out and hardened off before you put them out. In the mean time keep them in the garage near a window so they get sun. Hope that helps. Jason

[sbutler]

I'm going to take your advice and leave them inside. Thanks. I'll let you know how it works. Thanks again!
Steve
Zone 7a