When And How To Prune + Root Prune My Silver Maple Tree?

[Tinybird420]

Hello everyone. I have a silver maple pre-bonsai and I'm not sure when and how to prune her. (I live in NE Ohio zone 6a.) I've heard that you should prune maples in late winter right before spring, but what about root pruning? She's been in a 5 gallon pot (10"D x 12"W x 10.5"H) for a year now. I'm thinking of getting a grow box but IDK.

My plan for this tree right now is to get her as big as I can, I prefer bonsai on the bigger side. I can't grow in the ground so I know she's gonna be in the pre-bonsai stage for a very long time. I'm in it for the long haul. I assume the process is going to be letting her grow, cut her back and root prune every few years, rinse and repeat for a long time. Is that right? Unfortunately I've lived in an apartment since the end of August that is north facing, (she's against a West facing wall), so she hasn't gotten much direct sunlight. I think she'll get more direct sun in this area come spring. But because she doesn't get much direct sun I'm kinda afraid to do any harsh pruning. She gets so little direct sun that I'm seriously considering putting her on our balcony with a outdoor grow lights lol IDK.

And on that note I have another question. Does anyone know a rough estimate of the percentage of roots needed to support x amount of foliage? I don't want to root prune and then leave too much foliage/branches etc. for the roots to be able to support. Does that make sense?

Thanks in advance for the help! And sorry some of the photos are a bit blurry.

 

[Dav4]

Spring time just when the buds are beginning to swell is a great time to root prune and perform cut backs on the canopy. The frequency of each action depends on current goals for the stock. If this were mine, I'd probably be working the roots and I'd be chopping the trunk very low every 1-2 years.
The biggest issue with low light level growing is lanky growth with long internodes and larger than normal leaves... both are already obstacles with Silver maples grown under favorable conditions.

 

[Tinybird420]

Spring time just when the buds are beginning to swell is a great time to root prune and perform cut backs on the canopy. The frequency of each action depends on current goals for the stock. If this were mine, I'd probably be working the roots and I'd be chopping the trunk very low every 1-2 years.
The biggest issue with low light level growing is lanky growth with long internodes and larger than normal leaves... both are already obstacles with Silver maples grown under favorable conditions.

Thank you! How high above the soil would you chop?

Also isn't the other issue with low light that they won't be able to heal from wounds/diseases etc. as well?

 

[Dav4]

Thank you! How high above the soil would you chop?

Also isn't the other issue with low light that they won't be able to heal from wounds/diseases etc. as well?

I'd chop to one of the lowest branches. As far as healing from trauma, that is directly related to vigor and the presence or absence of strong growth. Strongly growing trees will callus over chop wounds and grow new roots faster than trees growing less strongly.

 

[Tinybird420]

I'd chop to one of the lowest branches. As far as healing from trauma, that is directly related to vigor and the presence or absence of strong growth. Strongly growing trees will callus over chop wounds and grow new roots faster than trees growing less strongly.

Cool thank you so much!

 

[Orion_metalhead]

I repot my maples here in 7b in early march typically, just as buds are starting to swell, as Dav said. Youd likely be mid march but watch the tree for signals.

Pruning is done for many reasons. If your goal is growth, I wouldnt prune the top at all. Id just repot into a grow box, removing no more than 50% of roots. Maples can take strong reductions of roots when properly timed but it slows them down a bit in the first year. This is sometimes necessary to generate better finer roots to power the tree later on.

Ive found silver maples need 100% full sun to get reduction in leace size.

Your tree has zero interest right now so chopping very low to a known internode is probably best course of action. Id do this after 1st flush in mid spring personally. For me, this is about late april, early may.

 

[Ininaatigoons]

Gotta do major cuts during the 2nd half of the last waning moon before the buds pop.
I always prune mine just before bud break and this is when roots are pruned also.

 

[Tinybird420]

I repot my maples here in 7b in early march typically, just as buds are starting to swell, as Dav said. Youd likely be mid march but watch the tree for signals.

Pruning is done for many reasons. If your goal is growth, I wouldnt prune the top at all. Id just repot into a grow box, removing no more than 50% of roots. Maples can take strong reductions of roots when properly timed but it slows them down a bit in the first year. This is sometimes necessary to generate better finer roots to power the tree later on.

Ive found silver maples need 100% full sun to get reduction in leace size.

Your tree has zero interest right now so chopping very low to a known internode is probably best course of action. Id do this after 1st flush in mid spring personally. For me, this is about late april, early may.

Thank you! So basically you think I should repot and root prune right as the buds are developing, and then chop to the lowest internode after the first flush of growth appears? Should I do this every 1-2 years then?

 

[Tinybird420]

Gotta do major cuts during the 2nd half of the last waning moon before the buds pop.
I always prune mine just before bud break and this is when roots are pruned also.

Ooh giving me the moon timeframe is pretty interesting, ty!

 

[Orion_metalhead]

Thank you! So basically you think I should repot and root prune right as the buds are developing, and then chop to the lowest internode after the first flush of growth appears? Should I do this every 1-2 years then?

Id do the hard chop back the year after repot and Id pump the tree up with heavy fertilization the previous year. A hard chop should be a planned action. Id do it if the trunk thickness is approaching what youre happy with. You do it not as the first flush is appearing, but as the first flush is hardening off.

 

[Tinybird420]

Okay that makes sense. And if it's not thick to my liking yet for many years I just leave it be until it is? (Besides root pruning obviously.)

 

[Orion_metalhead]

Then maybe, given your situation and inability to ground grow, maybe take a different approach and treat as a shohin so you can enjoy developing branches and such.

Otherwise, get it into grow box and grow, grow, grow. Maples can thicken pretty well in grow boxes. You might want to start developing a new leader down low if possible for cut back later and treat top as a sacrifice... i have done this with my linden:

Thread 'Tilia Cordata (Linden) #1'

Nov 10, 2019

Linden I dug from a customer's garden I was cleaning up this spring.

I like the overall shape. Need to determine what Im going to aim for next year.

Age: 2yr?
Training 1yr
Width: .25"
Height: 4"

• Orion_metalhead
• linden tilia cordata
• Replies: 45
• Forum: Other Deciduous

 

[Tinybird420]

Then maybe, given your situation and inability to ground grow, maybe take a different approach and treat as a shohin so you can enjoy developing branches and such.

Otherwise, get it into grow box and grow, grow, grow. Maples can thicken pretty well in grow boxes. You might want to start developing a new leader down low if possible for cut back later and treat top as a sacrifice... i have done this with my linden:

Thread 'Tilia Cordata (Linden) #1'

Nov 10, 2019

Linden I dug from a customer's garden I was cleaning up this spring.

I like the overall shape. Need to determine what Im going to aim for next year.

Age: 2yr?
Training 1yr
Width: .25"
Height: 4"

• Orion_metalhead
• linden tilia cordata
• Replies: 45
• Forum: Other Deciduous

That's a good idea ty.

Ooh I've never heard of Lindens before, they have such pretty leaves. Your tree is beautiful! Thank you for sharing .

 

[Ininaatigoons]

Pond baskets are used by some for training young trees. Along with self-made wooden grow boxes I have been trialing the bigger plastic wicker style containers.

 

[Orion_metalhead]

Pond baskets are used by some for training young trees. Along with self-made wooden grow boxes I have been trialing the bigger plastic wicker style containers.

I wouldnt use a pond basket for a maple - too drying. Wooden boxes are ideal I find. Pond baskets are great for juniper and pine.