I've just finished repotting two young trees I purchased from the bonsai nursery; a Japanese larch and a Chinese Elm. Though this is my first time potting anything in a bonsai soil mix I'm fairly confident I've done so correctly. I've read, on this site, that once a tree has been repotted that it should be protected from strong winds and the sun for about two months. The wind part is obvious but how much should I reduce the sunlight? Zero direct sun? Filtered sunlight? Bright but no direct light? What are people's opinions on this?

It is very late to be repotting Larch. It is risky once they are in full leaf. The protection needed is from frost and winds for 2 or 3 weeks, then they should be fine. Fertiliser can be started after about 4 weeks.Full sun if fine as long as they do not dry out.

Thanks for your reply... Hopefully I haven't doomed my new tree by repotting too late. I had read that they can be repotted during Spring, just as the buds erupt. Also read that the timing is very tight and that you can't repot once the leafs extend much.

We had a very cold early Spring in my part of the world (Canada) so maybe that delayed the budding? The needles have only just erupted a few millimeters from the buds if that makes any difference

Well I don't know where in Canada you are from... but if you live in a very cold climate like I do, time for repotting is mid April to mid may... Some of us are not as lucky with temperate weather

I'm in Toronto; right on the boarder with USA. Generally we have mild Springs but this year was bitterly cold with lots of snow and freezing rain. Both the elm and larch seem to be doing very well so it seems I didn't mistreat them too badly

If it is doing well then you didn't do anything wrong. I don't know about that particular tree. But usually re-potting window is right before deciduous trees start budding until most small leaves are out. Regardless of weather patterns, best thing is to luck at trees on the area, if they are budding you know it is almost time. I think the best time to re-pot is somewhere in between, right when most deciduous trees have visible buds.

And honestly, you can re-pot any time during early growing season, and even during the growing season. It is just not good for the trees growth if you do it too late, or if you remove too many roots. I am not an expert though, so always follow the guidelines for those with years of experience.

eangola wrote:

And honestly, you can re-pot any time during early growing season, and even during the growing season. It is just not good for the trees growth if you do it too late, or if you remove too many roots. I am not an expert though, so always follow the guidelines for those with years of experience.

Hm.. Not sure I agree there. Certainly the larch you should not repot once the buds have started to open. All other plants.. Deciduous trees repotted after leafing out have a higher change of not surviving.

leatherback wrote:

eangola wrote:

And honestly, you can re-pot any time during early growing season, and even during the growing season. It is just not good for the trees growth if you do it too late, or if you remove too many roots. I am not an expert though, so always follow the guidelines for those with years of experience.

Hm.. Not sure I agree there. Certainly the larch you should not repot once the buds have started to open. All other plants.. Deciduous trees repotted after leafing out have a higher change of not surviving.

You're right, I don't know what I was thinking.