So all those Lillies are in tubs in your lake????Or do you remove them from the tub and allow them to root into the lake bottom? I have found the tubs greatly reduce the growing capacity of the plant, but maybe that's what you want.
Ultimately, they're in the lake. Almost all hybrid lilies are sold with bare roots. I like to start them out in tubs so they can acclimate to the weather and heal their roots. If I get a huge water drop, the tubs also allow me to move the lilies into deeper water. Yes, tubs do help control the spread of the lilies. Some can still spread via seeds, but not as fast. I planted a very slow spreading hybrid lily 3-4 years ago, and I'm seeing pop ups in several different areas in the pond.
Depth? I can't remember seeing any in water deeper than 3' , but most seem to do be denser and spread faster in the bank to 2' water.
