Hi, I don't have open ground to plant trees to grow thicker trunks. I have many trees and plants that are growing in their respective plastic gardening pots and they are putting on the growth that I expect but I was wondering if having a bigger pot helps. I've heard of slip potting but I just want to make sure I'm not wasting time or doubling my time for growing trees. When the option for me to grow in ground is available then I will do that.