As most of you know, roots circling around a container isn’t considered a good thing. And so people try various things to control circling roots. One of the more creative horticultural minds out there, Carl Whitcomb, a guy why basically got sick of academia and went into private industry (and, as far as I can tell, loathes peer review and the whole process of publication), decided to see what he could do about making containers that don’t encourage circling roots. He came up with a number of designs, but my favorite is the RootTrapper. The container is made of a flexible cloth which roots get lodged in, preventing them from circling. Not that I’ve never seen a circling root in a RootTrapper, it’s just that these circling roots are extremely rare.
A row of elms in RootTrappers
A cut open RootTrapper
This is one of those innovative products that really works and it surprises me that so few people use this growing system. Yes, it’s a bit more expensive than standard containers, and yes, it does take a little more effort to take the tree out of this container than a smooth sided one. But man, I’ve never seen a better root system come out of a container than those which you get out of these.