About two weeks ago I carried out a spring fertilizing with growmore, and today I see some plants struggling. As for my hydranger, about two feet tall now, its new shoots are turning black and melting down. My thymes are turning black. My lavendars look dead, with no shoots but just stems brown inside out. But there are other plants doing fine. I was trying to figure out what is going on and realized that I gave too much growmore.

To hydranger and lavendars I gave a fistful and piled it up mostly around the center of the plant. To thyme I gave much less but poured it right in the center. Is this too much? Then can you tell me what is the right amount?

Thank you very much.