My plan was to take the lid off and attach some burlap, and that would be the drainage system. Less holes than a regular pot but due to the shape (funnel like) it would make up for it. I want to maximize the length of the bottle, and perhaps even allow for some "air pruning" like a smart pot.
I want to put them in trees. Specifically pine trees. Between two branches, attached to the trunk with above branches adjusted to allow the arching sun of northern countries to reach it all day. Only about 3 to 6 feet off the ground but free from animals and void from the view of anyone not standing directly in front.
Get some camo tape used for gunstocks and wrap the bottles for a little more stealth.