Avocado roots grow fast, and young trees like to grow fast. Avocados are native to rainforests and cloudforests on the side of mountains, and young seedlings usually grow in complete shade beneath their mother tree. So, they like to quickly push to break the canopy and get some sun. In this video, I experiment with some decomposed granite as my potting mix. The results are interesting!

The decomposed granite seemed to hold a lot of water and it took a long time to drain, but the tree didn't mind!