Disproportionate Dawn Redwood

[dtkabardin]

I have had redwood since July, and wondering if I can get some help developing a plan for this tree. Currently in a 5 gal pot. I think it needs to be repotted to a shallower grow box, the trunk is too thin, and seems the branches are already too thick for the trunk.
I’m not sure where to start and don’t want to do too much at once.
I’d like it to be a typical upright coastal redwood style.
What would you do with this tree this year and the next to get closer to that goal?
I’m in Sacramento, CA.

 

[Shibui]

Trunk thickening does not come from a shallow container. Shallow container may help produce a shallow root system but not always shallow enough for a bonsai pot so you will still need to root prune at some stage.
Thickening comes from growth above any given section of trunk so allowing lots of growth is the best option to hasten thickening. The other key to thickening trunks is patience. You've only had the tree a few months. I've been growing some for 10 years and more to develop the trunks I want.
Basal flare is one aspect of trunk thickening. Dawn Redwood do that very well when allowed to. I've found that basal flare is directly related to strong, radial surface roots in all species I've worked with. To help with that I'd be unpotting at the appropriate time of year and pruning the roots aggressively. Remove ALL roots growing down as short as possible. Then shorten all laterals which should encourage them to ramify. Encouraging the laterals while discouraging down roots not only prepares your tree for life in a bonsai pot but also encourages basal flare. After a couple of rounds of such pruning the trees seem to settle down and rely on the laterals and grow very few down roots.

Thick branches seem to be a feature of trees grown fast for maximum thickening. The cure is to remove the thicker branches. Most trees will grow new shoots from the base of pruned branches allowing you to grow new ones in a more controlled way.

You will also need to reduce the main trunk at some stage to add some taper. At the moment your tree has youthful characteristics - tall, skinny trunk with no taper. Producing a trunk with taper gives the impression of a much older tree.

 

[Gabler]

Trunk thickening does not come from a shallow container. Shallow container may help produce a shallow root system but not always shallow enough for a bonsai pot so you will still need to root prune at some stage.
Thickening comes from growth above any given section of trunk so allowing lots of growth is the best option to hasten thickening. The other key to thickening trunks is patience. You've only had the tree a few months. I've been growing some for 10 years and more to develop the trunks I want.
Basal flare is one aspect of trunk thickening. Dawn Redwood do that very well when allowed to. I've found that basal flare is directly related to strong, radial surface roots in all species I've worked with. To help with that I'd be unpotting at the appropriate time of year and pruning the roots aggressively. Remove ALL roots growing down as short as possible. Then shorten all laterals which should encourage them to ramify. Encouraging the laterals while discouraging down roots not only prepares your tree for life in a bonsai pot but also encourages basal flare. After a couple of rounds of such pruning the trees seem to settle down and rely on the laterals and grow very few down roots.

Thick branches seem to be a feature of trees grown fast for maximum thickening. The cure is to remove the thicker branches. Most trees will grow new shoots from the base of pruned branches allowing you to grow new ones in a more controlled way.

You will also need to reduce the main trunk at some stage to add some taper. At the moment your tree has youthful characteristics - tall, skinny trunk with no taper. Producing a trunk with taper gives the impression of a much older tree.

This ^^^

 

[dtkabardin]

Thanks for the valuable info! It sounds like right now, my main focus should be to root prune the tree’s vertical roots and let the entire tree grow out. Should I keep the thick branches to help with trunk thickening, or eliminate them to help scars heal faster? I’m guessing this is a trade off I have to commit to. Either have a thicker trunk with larger scars or a less scars and a thinner trunk.
Ive been reading up a lot on ground growing vs pot growing for trunk thickening and my only option is pot growing. Would you recommend a larger grow box or maybe Anderson flat, or something else?

 

[Gabler]

I’m guessing this is a trade off

Exactly. Large sacrifice branches will get you a thick trunk faster, but the chop wounds will struggle to heal, and even when they do, the scars will be obvious.

 

[Shibui]

Exactly. Large sacrifice branches will get you a thick trunk faster, but the chop wounds will struggle to heal, and even when they do, the scars will be obvious.

Well put. Some people will choose the fast growth and hope the scars will heal. Others will prefer less scarring but longer development time.

Ive been reading up a lot on ground growing vs pot growing for trunk thickening and my only option is pot growing. Would you recommend a larger grow box or maybe Anderson flat, or something else?

Container growing is a good option. It may take a few extra years but you have way more control and therefore less chances of undesirable outcomes.
Anderson Flat is the current go to but I suspect that's only because most growers are not yet comfortable with root pruning. I find a slightly deeper container gives better growth and root pruning manages the roots better than the roots just being limited by a shallow tray.

 

[Gabler]

I use shallow containers, but I put them on the ground, where the roots can escape. In the spring, I pick them up to sever the roots. From time to time, I do still need to repot to work on the nebari, but it's a bit less work in the meantime.