Late summer repotting

Lazylightningny

Masterpiece
Messages
2,257
Reaction score
2,105
Location
Downstate New York, Zone 6b
USDA Zone
6b
Maybe the same? It was a while ago, international erosion control bioengineering conference. The may have been Austrian and they did call it rhizo-somethingorother, I don’t remember. Mostly I just remember beIng surprised at the growth of conifer roots over winter in the mountains, at the time I thought there wouldn’t be much happening. My own trees stay frozen solid for many months here being shallowly mulched but I imagine folks in warmer places get root growth over winter in pots.
I'm going to retire somewhere south with a longer growing season. New York is bad enough, I can't imagine having just a few good months of growing.
 

sorce

Nonsense Rascal
Messages
32,908
Reaction score
45,579
Location
Berwyn, Il
USDA Zone
6.2
Except that doesn’t always work. In the Yukon where I used to live, the growing season doesn’t start until very late. In Whitehorse the last spring frost is June 12.

We would have to make it work.
9 days till the solstice.

100/9=11.11 points per day.

Our lingo would involve these points per day.....

Accidental post dispatch..... more.

Sorce
 

Forsoothe!

Imperial Masterpiece
Messages
6,878
Reaction score
9,248
Location
Michigan
USDA Zone
6b
Snow, especially deep snow is an insulator against the deep cold air. When and where heavy snow blankets land (mostly mountainsides) before the earth freezes, or freezes deeply, it can take a long time for deeply cold air to cool the snow which can then cool the earth. The Air Force used to teach airmen to dig a hole in deep snow for protection against deep cold air if they had to bail out of their plane in the mountains. Snow is basically ~32°F and transfers heat/cold poorly, changing slowly.
 

wireme

Masterpiece
Messages
3,671
Reaction score
8,238
Location
Kootenays, British Columbia
USDA Zone
3
Snow, especially deep snow is an insulator against the deep cold air. When and where heavy snow blankets land (mostly mountainsides) before the earth freezes, or freezes deeply, it can take a long time for deeply cold air to cool the snow which can then cool the earth. The Air Force used to teach airmen to dig a hole in deep snow for protection against deep cold air if they had to bail out of their plane in the mountains. Snow is basically ~32°F and transfers heat/cold poorly, changing slowly.

This was my home for a month at 4200m in the Himalayas one time...
C14FF10B-445E-4172-92B1-71C2CA0285CA.jpeg

Not gonna say I never got cold but still alive!
 

sorce

Nonsense Rascal
Messages
32,908
Reaction score
45,579
Location
Berwyn, Il
USDA Zone
6.2
Damn...so yeah....of winter roots and snow.

Had this notion that time or temp doesn't matter.
And it may not.

If a tree must (after fall repot) it'll probly grow roots straight through the winter if well snow covered.

@Smoke how's that hot potted tree?

Sorce
 

Maloghurst

Chumono
Messages
750
Reaction score
1,096
Location
Seattle WA
USDA Zone
8b
Damn...so yeah....of winter roots and snow.

Had this notion that time or temp doesn't matter.
And it may not.

If a tree must (after fall repot) it'll probly grow roots straight through the winter if well snow covered.

@Smoke how's that hot potted tree?

Sorce
I’m actually really liking this discussion (most of the time). And your thoughts are accurate for a mild repotting such as was done in the original post. Seems like its actually better if lightly repotting in fall so in spring it can hit the ground running!
I will definitely do it with some of mine.
But time and temp does matter for root growth.
Roots, like shoots, grow most rapidly when temperatures are moderate-between 20 and
30 degrees C (68 and 85 F) (Russell, 1977). So I ask would you do Major root work on a maple in fall? Where you reduce 70% of a root mass? You can do this in spring with a high degree of success because maximum root growth for maples is late spring early summer.
 

M. Frary

Bonsai Godzilla
Messages
14,307
Reaction score
22,116
Location
Mio Michigan
USDA Zone
4
And thru the summer if not too hot.

If there are "periods", it's every moon.

I would love to see the natural conditions in which these said root growth "periods" are observed.🤔

Sounds completely made up at best.

Trees are more opportunistic than stupid.

Sorce
My trees start growing in spring and dont let up until the leaves fall off.
Roots and foliage.
No "flushes"
Just grow.
It's a touch cooler up here and the season is short.
The trees know this and make hay while they can.
 
Last edited:

Forsoothe!

Imperial Masterpiece
Messages
6,878
Reaction score
9,248
Location
Michigan
USDA Zone
6b
Three principles for me are: the tree has to have enough growing time left in the season of major work to recover before quiescence, and, don't work on top and bottom in the same season, and the tree needs all the resources it can to recover, so I don't work the roots if defoliated, and I want the whole canopy to be healthy, mature and present when I do major root reduction. Mid to late June is my first choice to do all these things, with July second best, and early August third choice.

I don't like autumn for root work, maybe because I have had poor results. Trees go to sleep and never wake up. I don't like early spring because removing roots just when the canopy needs the resources of the roots to inflate a whole bunch of leaves doesn't make sense to me.
 

_#1_

Omono
Messages
1,025
Reaction score
1,274
Location
Houston, TX
USDA Zone
9a
Yes, and the usefulness of the leaves and sun (to the extent that JM are exposed) for growth of replacement roots.
Isn't that a catch 22? Chopping off half the roots with a full canopy? And exposed to sun? What about transpiration and not enough roots to sustain all the leaves?
 

Walter Pall

Masterpiece
Messages
3,619
Reaction score
20,305
Location
south of Munich, Germany
USDA Zone
7b
Isn't that a catch 22? Chopping off half the roots with a full canopy? And exposed to sun? What about transpiration and not enough roots to sustain all the leaves?

One of the best things about late summer potting: 'Yo leave the full canopy - do not cut roots and folate at the same time. You can cut roots, but you do not always have to. Don't forget that root cutting is severely weakening a tree. But if you have to and leave the full canopy new roots will grow much quicker than in spring. In spring the tree puts all it's strength into new foliage. If you then cut roots the tree has to make a decision here and divide it' strength. There is no new energy coming from the non-existing mature foliage and the new roots have to be fed from energy that was meant for foliage.



Sure you expose the canopy to full sun after late-summer repotting. Temperatures will go down quickly , days are shorter. The full sun on mature foliage will create energy to get lots of new roots quickly. The evaporation is there, but it's getting better every day.

In my garden the very best time is exactly now. In other gardens it will be one or two weeks or more later or even earlier. You have to figure out yourself.



This is why late summer repotting is the safest, saver than spring repotting. Also when you do root work. This is why I recommend to forget everything you thought you knew.



The full foliage is also important in spring for the same reason. This is why I advocate to pot as late as possible in spring with foliage already out for most trees. The full foliage which is not cut at the same time will send growing hormones to the roots (auxin) with the message 'grow fast everything is OK here I can support much more roots and need them). If you cut foliage the foliage would not send the message and as a s result the tree is not quite sure what to do.



Attached you see late summer (beginning of August) repotting of Japanese maple and trident maple And then spring repotting of Japanese maple. As one can see this is accompanied with heavy root pruning. So the claim that this man is southern Germany only buys top Japanese trees and repots them with no root work is ridiculous and exposes the writer as ignorant. These trees were exposed to full sun and grew happily after that.

These were absolutely not emergency repots. I could have chosen any day of the year. Does someone really think that I do all this just to show off how different my methods are? Would it not make much more sense that I do this with precious trees because it is the best for them.

All this information was written several times already in the past years. So the push to write it again is annoying and shows disrespect of my efforts. If you want something from me you have to do your homework first.


2018-08-TSA_4059w.jpg2009-03-DSC_5909v.jpg2017-08-SAL_9877w.jpg
 
Last edited:

Palmer67

Yamadori
Messages
58
Reaction score
51
Location
Lake Stevens WA
USDA Zone
8A
One of the best things about late summer potting: 'Yo leave the full canopy - do not cut roots and folate at the same time. You can cut roots, but you do not always have to. Don't forget that root cutting is severely weakening a tree. But if you have to and leave the full canopy new roots will grow much quicker than in spring. In spring the tree puts all it's strength into new foliage. If you then cut roots the tree has to make a decision here and divide it' strength. There is no new energy coming from the non-existing mature foliage and the new roots have to be fed from energy that was meant for foliage.



Sure you expose the canopy to full sun after late-summer repotting. Temperatures will go down quickly , days are shorter. The full sun on mature foliage will create energy to get lots of new roots quickly. The evaporation is there, but it's getting better every day.

In my garden the very best time is exactly now. In other gardens it will be one or two weeks or more later or even earlier. You have to figure out yourself.



This is why late summer repotting is the safest, saver than spring repotting. Also when you do root work. This is why I recommend to forget everything you thought you knew.



The full foliage is also important in spring for the same reason. This is why I advocate to pot as late as possible in spring with foliage already out for most trees. The full foliage which is not cut at the same time will send growing hormones to the roots (auxin) with the message 'grow fast everything is OK here I can support much more roots and need them). If you cut foliage the foliage would not send the message and as a s result the tree is not quite sure what to do.



Attached you see late summer (beginning of August) repotting of Japanese maple and trident maple And then spring repotting of Japanese maple. As one can see this is accompanied with heavy root pruning. So the claim that this man is southern Germany only buys top Japanese trees and repots them with no root work is ridiculous and exposes the writer as ignorant. These trees were exposed to full sun and grew happily after that.

These were absolutely not emergency repots. I could have chosen any day of the year. Does someone really think that I do all this just to show off how different my methods are? Would it not make much more sense that I do this with precious trees because it is the best for them.

All this information was written several times already in the past years. So the push to write it again is annoying and shows disrespect of my efforts. If you want something from me you have to do your homework first.


View attachment 257343View attachment 257344View attachment 257345
This just makes sense and it's very logical. I tried your hedge cutting method for my maples and have seen stellar results. I'm on board with this. Thank you!
 

Maloghurst

Chumono
Messages
750
Reaction score
1,096
Location
Seattle WA
USDA Zone
8b
I don't think anyone should, even if they've been "successful".

Late Summer. That is the time.

We musn't fear the heat.

Sorce
I’m sorry I misspoke, I meant late summer as well Thanks for answering my question.
One of the best things about late summer potting: 'Yo leave the full canopy - do not cut roots and folate at the same time. You can cut roots, but you do not always have to. Don't forget that root cutting is severely weakening a tree. But if you have to and leave the full canopy new roots will grow much quicker than in spring. In spring the tree puts all it's strength into new foliage. If you then cut roots the tree has to make a decision here and divide it' strength. There is no new energy coming from the non-existing mature foliage and the new roots have to be fed from energy that was meant for foliage.



Sure you expose the canopy to full sun after late-summer repotting. Temperatures will go down quickly , days are shorter. The full sun on mature foliage will create energy to get lots of new roots quickly. The evaporation is there, but it's getting better every day.

In my garden the very best time is exactly now. In other gardens it will be one or two weeks or more later or even earlier. You have to figure out yourself.



This is why late summer repotting is the safest, saver than spring repotting. Also when you do root work. This is why I recommend to forget everything you thought you knew.



The full foliage is also important in spring for the same reason. This is why I advocate to pot as late as possible in spring with foliage already out for most trees. The full foliage which is not cut at the same time will send growing hormones to the roots (auxin) with the message 'grow fast everything is OK here I can support much more roots and need them). If you cut foliage the foliage would not send the message and as a s result the tree is not quite sure what to do.



Attached you see late summer (beginning of August) repotting of Japanese maple and trident maple And then spring repotting of Japanese maple. As one can see this is accompanied with heavy root pruning. So the claim that this man is southern Germany only buys top Japanese trees and repots them with no root work is ridiculous and exposes the writer as ignorant. These trees were exposed to full sun and grew happily after that.

These were absolutely not emergency repots. I could have chosen any day of the year. Does someone really think that I do all this just to show off how different my methods are? Would it not make much more sense that I do this with precious trees because it is the best for them.

All this information was written several times already in the past years. So the push to write it again is annoying and shows disrespect of my efforts. If you want something from me you have to do your homework first.


View attachment 257343View attachment 257344View attachment 257345
Thank you Walter, Im realizing that all the root studies in the world are good info to know but do not necessarily mean as much when you are dealing with Bonsai.

One last question, do you collect your hornbeam and beech etc in late summer as well? Not technically repotting so just looking for clarification. I’m apologize if this info is covered elsewhere, a simple yes or no will suffice.
Thank you
 
Last edited:

Walter Pall

Masterpiece
Messages
3,619
Reaction score
20,305
Location
south of Munich, Germany
USDA Zone
7b
One last question, do you collect your hornbeam and beech etc in late summer as well? Not technically repotting so just looking for clarification. I’m apologize if this info is covered elsewhere, a simple yes or no will suffice.
Thank you

I personally would collect these trees in spring. The reason is that one needs very good frost protection after collecting. I cannot provide this as I have almost 1000 trees and no possibility of save overwintering for extra ones. My Croatian students in Dalmatia, which is at the sea, collect in November and December, sometimes in January and February. They do not need super protection in winter as palm trees are growing close by.
 

Maloghurst

Chumono
Messages
750
Reaction score
1,096
Location
Seattle WA
USDA Zone
8b
I personally would collect these trees in spring. The reason is that one needs very good frost protection after collecting. I cannot provide this as I have almost 1000 trees and no possibility of save overwintering for extra ones. My Croatian students in Dalmatia, which is at the sea, collect in November and December, sometimes in January and February. They do not need super protection in winter as palm trees are growing close by.
Thank you!
 

sorce

Nonsense Rascal
Messages
32,908
Reaction score
45,579
Location
Berwyn, Il
USDA Zone
6.2
This is my favorite part. The Nugget that really stuck with me when I met Walter.

it's getting better every day.

Why, of course!

Not only is energy divided in spring, but weather is getting hotter, worse, and as many of us know, early heat can be just as, or even more fatal then a late frost.

A late frost which, by the way, I believe a tree knows is coming. So if you repot 2 weeks before the last frost in spring, the tree won't be growing roots for 2 weeks.

Whereas in Late Summer, if you are set for an early frost in fall, the tree also knows this, so it will begin to grow roots like mad, even through the frost, because foliage is also mature, hard, capable of withstanding the cold.

In order to best work WITH a tree, you must realize how smart they are. Their will to live is great, in nature, Never as Bonsai.

We have to remember to do best by the tree as if it were in the ground, as if it were ....
Natural!

Aha! Uncovering the secrets of "naturalistic bonsai", it was never a design style!
Hehehehehe!

Where's the moon at? Bout to get to repotting!

Sorce
 

Cable

Omono
Messages
1,371
Reaction score
2,188
Location
Sheffield Village, Ohio
USDA Zone
6a
One of the best things about late summer potting: 'Yo leave the full canopy - do not cut roots and folate at the same time. You can cut roots, but you do not always have to. Don't forget that root cutting is severely weakening a tree. But if you have to and leave the full canopy new roots will grow much quicker than in spring. In spring the tree puts all it's strength into new foliage. If you then cut roots the tree has to make a decision here and divide it' strength. There is no new energy coming from the non-existing mature foliage and the new roots have to be fed from energy that was meant for foliage.



Sure you expose the canopy to full sun after late-summer repotting. Temperatures will go down quickly , days are shorter. The full sun on mature foliage will create energy to get lots of new roots quickly. The evaporation is there, but it's getting better every day.

In my garden the very best time is exactly now. In other gardens it will be one or two weeks or more later or even earlier. You have to figure out yourself.



This is why late summer repotting is the safest, saver than spring repotting. Also when you do root work. This is why I recommend to forget everything you thought you knew.



The full foliage is also important in spring for the same reason. This is why I advocate to pot as late as possible in spring with foliage already out for most trees. The full foliage which is not cut at the same time will send growing hormones to the roots (auxin) with the message 'grow fast everything is OK here I can support much more roots and need them). If you cut foliage the foliage would not send the message and as a s result the tree is not quite sure what to do.



Attached you see late summer (beginning of August) repotting of Japanese maple and trident maple And then spring repotting of Japanese maple. As one can see this is accompanied with heavy root pruning. So the claim that this man is southern Germany only buys top Japanese trees and repots them with no root work is ridiculous and exposes the writer as ignorant. These trees were exposed to full sun and grew happily after that.

These were absolutely not emergency repots. I could have chosen any day of the year. Does someone really think that I do all this just to show off how different my methods are? Would it not make much more sense that I do this with precious trees because it is the best for them.

All this information was written several times already in the past years. So the push to write it again is annoying and shows disrespect of my efforts. If you want something from me you have to do your homework first.

That's a really great explanation, thank you. I was debating whether or not to cut back the canopies on the three jap maples I just repotted but I decided not to and this reinforces my choice.
 

BunjaeKorea

Omono
Messages
1,214
Reaction score
1,909
Location
Korea
USDA Zone
7a
I think this really depends where you are. In Korea, China and Japan they re-pot flowering (Japanese) quince in late Autumn or Early winter to prevent the fungal spread of Quince root canker which spreads like mad in spring if you cut roots. The locality should impact on what techniques are used so the principles for doing re-potting may change depending of variables.
 
Top Bottom