First day of Winter; should I repot?

[Clicio]

Here in the Southern hemisphere it's winter time from now on. Our winters are mild and very dry.
I have this young JBP that needs to go into a grow box much bigger than the pot it's being kept; is it too risky to repot it now (no wiring, no pruning) ? The alternative being to repot it first days of Spring.

 

[0soyoung]

Look for the buds to start pushing --> then.

 

[Clicio]

Look for the buds to start pushing --> then.

Yes.Thanks.
I have repotted pines before, and always following the "when buds start to swell" rule.
But...
In Japan, where winters are also dry, some growers repot pines by the end of fall. And some nurseries in Brazil do the same, repotting in the fall.

 

[Wires_Guy_wires]

I'm not sure about Brazil, but I repotted some JBP at the end of summer and they are fine almost a year later.
You don't get any frosts at all, right?

I'm thinking out loud here, hoping someone more experienced with JBP jumps in:
The tree is dormant from winter until the end of spring, it only grows a little in that time. Then why should it matter if there's damage now, or later in the dormancy?
I can see there's a chance of infection, sure, in wet winters. In dry winters, those pathogens usually start thriving in spring. But if this pine is repotted now, the damage might have been healed by the time it's spring again.
If the aim is to 'minimize time being damaged' I'd say that Brazil winters are better than Brazil springs - to my understanding those are 'rainy season' type springs. If the aim is to 'do the damage as close to restoration' then I'd say spring is better.

Is it a strong and vigorous tree?

 

[0soyoung]

Yes.Thanks.
I have repotted pines before, and always following the "when buds start to swell" rule.
But...
In Japan, where winters are also dry, some growers repot pines by the end of fall. And some nurseries in Brazil do the same, repotting in the fall.

Well then, do it and let us know how it went.

Fall for me is after the autumnal equinox and before the winter solstice (today).
The issue is whether it is 'active' and has the capacity to regrow root tips. I repot in summer and early fall. My winters are generally mild, but below 40F/5C for most of the hours of the day. Your location, on the other hand never gets that cold so maybe it works out okay. It will be interesting to know.

 

[BackyardBonsai]

Question??? what do you get out of the repot it now rather than wait until bud start to move? If you just want to experiment then do it.

 

[Clicio]

I'm not sure about Brazil, but I repotted some JBP at the end of summer...
Is it a strong and vigorous tree?

Thanks, yes it is quite healthy and has grown a lot this past season.
I think I will try. Let's see.

 

[LanceMac10]

….why change a routine you have success with.....


....is there a benefit....


let us know how it goes.

 

[Clicio]

Fall for me is after the autumnal equinox and before the winter solstice (today).

Yes, that's why I have asked, I was hoping you would jump in and I'm glad you did.
If it were last week I wouldn't mind repotting but after winter solstice, I am not so sure.

Your location, on the other hand never gets that cold so maybe it works out okay. It will be interesting to know.

I think I will try anyway, thanks!

 

[BonsaiMatt]

If it were last week I wouldn't mind repotting but after winter solstice, I am not so sure.

Why so obsessed with repotting on a schedule? Does the tree care about a few minutes +/- on sunset times?

 

[0soyoung]

Why so obsessed with repotting on a schedule? Does the tree care about a few minutes +/- on sunset times?

A few minutes is nothing, of course. But trees' growth patterns are different when days are getting longer versus when they are getting shorter. Trees register the passage of the summer solstice within 3 weeks of its actual occurrence (as measured by the rate of stem thickening with a $15 caliper). It is just amazing to me that they are that accurate. IOW, anytime within the next couple of weeks is the same thing as fall for trees in the Southern hemisphere (spring for us in the Northern) even though today is the solstice that affects the dividing line.

 

[jason biggs]

@Clicio we only have a month of winter left so go big...
zone 11a - shouldn't make too much difference if you repot now...
our mid winter is warmer than most northern hemisphere spring temps

 

[Shibui]

Maybe there's a big difference between cool temperate and milder winters.
We have had -4.5C for the last couple of mornings and that's cold for here.
I repot and root prune maples from leaf drop through to leaves opening with no losses. I generally leave the evergreens till later in spring but I have no real reason why. I suspect they would do just as well as the deciduous trees if root pruned now, especially as many do not really seem to go fully dormant in this climate.
Your results will be great to add to the bonsai body of knowledge for others in mild climates.