Limiting tree size via container size
If I've understood correctly, one way to assist (besides pruning!) in controlling the ultimate growth size of dwarf and semi-dwarf fruit trees is to put them in a container, thereby limiting the maximum size their root ball can reach.
Are there any rules of thumb regarding the size at which a fruit tree will basically stop growing (or at least slow down a good bit) as a function of container size?
(For example - and I'm making these numbers up - a 10 gallon container might encourage tree size to start maxing out at 8' tall and 6' wide, a 20 gallon at 11' tall and 9' wide, etc.)
Does anyone have any insights into this that they would care to share?
In particular, how effective (or ineffective) is this method?
(BTW, I'm thinking of using Smart Pots and expect that these would affect trees differently than regular containers due to air pruning. My guess is that they would be more effective at helping with size control.)