I have read that you can cover rhizomes with about an inch of soil in hot climates, and wondered if I should do that here in NC. BUT: I had a old clump of Acoma that were buried in soil under a tree in my back yard. They would bloom only sporadically, but once I pulled them up and planted them on top they took off like gangbusters. There was even a yellow noid buried that I never even knew was there! It is quite pretty and ruffly, but sure didn't grow before it was released from it's soil covering.
