The white seems even less invasive than the pink, but they do spread some. I love the white flowers so I let them stay at one side of the house.
Sorry to hear about the fish and damage. I managed to kill all but three of my goldfish (again). I just can't stay on task anymore. I stepped into the shop for the a/c and to put up the chemical. Sure didn't need to waste water in this drought either! I wish I could blame a raccoon on getting them. Something is coming to the pond at night driving my dogs nuts. They wake up about 5 or 5:30 wanting out and head straight for the pond. Could be tree rats, we have had them in the past. They would steal the Althea blooms.
