Used for idea of necessity I got tired of picking up the citrus tree every time the wind blew. Filling in the sides helps prevent (and stopped) a 14 inch Terra pot with a five foot citrus from wind knock over.

Right or wrong I didn't remove inner pot from the outer pot to water when watered I watered the inner pot.
None of us are sure how to direct rain fall yet but yes pot in pot does and is very useful to wick water out.

If there is to be a draw back to the pot in pot method I did remove the inner pot at season ending to indoors only to find root from the citrus had grown into the outer pot.

I think and would agree the same root would have grown into the ground and my citrus could have frozen.

Might not be the best idea for every plant but there are more benefits than draw backs especially for wind sailed subjects of both plants and trees.

Thanks for the reply.

As soon as I get some more pots, I'm gonna try the pot-on-pot method to see if I can get results.

Z