Geotextile retaining wall bags makes great container
I had some left over geotextile bags that you fill with soil and stack to make large retaining walls that flex, breathe, let the water through and will support native vegetation. I wanted to plant a fig tree this year in my front yard but I had a couple problems, the area hasn't been graded yet properly, and we have heavy clay soil here in Southern California, solution, raised bed. Instead I decided to use these bags that measure 18"x36", stack them in a circle to basically make a container. The picture really doesn't do it justice how big that is, but there are 8 bags filled with a mix some where between a Gritty and 5-1-1, great for growing and drains well. I made so much mix that I used a cement mixer to mix it, took three batches to fill each bag, plus had to fill the whole center. I'm so happy with it, the fig seems to love it. I had to stake up the side branches because we had Santa Ana winds that usually blow about 50-60 mph blow them over, so we staked them back up.
Anyway, people are always asking about grow bags, this is my home made version.