Maiden69
Masterpiece
Here is my take... don't get a 5 gal container. Get something like what Bill is using on the below picture in the middle trees. This is what I am using this spring for my biggest BC, which will be on it's 4th year this coming spring. I set my trees on a tile and inside a Rootpouch, but with this years experience I can tell you that if you use a pouch, you need to oversize it as BC's push roots like no other tree I own.I see your point about longer growth. Maybe repot in 5 gallon this spring and let it grow some more?
I would repot your tree this spring, as soon buds start to swell. You don't need to use any organic media, I use monto clay and bonsai block from Bonsai Jack inside my bag, I then place the bag inside the tub and fill the void with water. My tree stays in water all year round, including winter, but we only experience a week of very cold weather, and as Brent Watson said, the roots and trees do better frozen in water than dry in freezing wind.
Depending on how the roots on your tree look, I wouldn't root prune too much, just tease as much of the old soil you can and spread them out as best as you can. Use the ramification you have now to help the tree recover as fast as possible this year, then trunk chop next spring.
If you place it in a bigger container without managing the roots you will end up with a pretzel of roots that are good for nothing... ask me how I know
Here is a link to my BC progression... I should be updating it again soon. I am waiting on a shipment with a few more seedlings to experiment this year, should be fun to put in practice a few theories I have come up with growing this first batch for 2 years.
Bald Cypress group progression
I have 4 BC seedlings that I bought in March. They are all planted in inorganic soil, they do have 1/3" akadama, but that was not enough to keep them growing so I submerged the pots in water. I lost 2 to a hail storm. The other 3 are pictured here in order of time. The last one is a 1 gal tree I...
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