For lilies I've used a variety of pots and the best results have always came from solid pots.
I use cheap dishpans for potting or something similar to the size.
Last year I even used the shallow whiskey barrels for my Colorado and Barbara Dobbins and they bloomed like crazy.. lots of room! BUT some can't do that because they need room for their other lilies!
I've used alot of different potting materials. Clay out of my yard, Composted Manure, Kitty Litter, etc.. to date I've not noticed much of a difference. Last year I used all kitty litter and they grew just as well as the others planted.
I believe either Marilyn C, Craig or Sean turned me onto Osmocote, so that's what I've been using for the past several years. You can't go wrong!
Osmocote 14-14-14 or Multicote (can't recall which but it's the highest double digit formula)
The only time I use fertilizer tabs are once, in the beginning of the season due to the fact that it takes awhile for time released to break down....
Curious what works best for you???????
Thanks for sharing,
Bonnie