I am doing something dreadfully wrong with my baskets of petunias. Every single year without fail, the stems underneath the top layer get brown leaves and then become extremely leggy. I water them daily in the morning, I use Osmocote, and they are all in spots where they get a good amount of sun. I see some of the municipal baskets with long luxuriant petunia plants that look three feet long and healthy as can be. Anyone have ideas?