I am really no help in this conversation, and I am the one that every year has not done the magic elixir on seedlings. I believe last year I did use it a total of two times and then life got in the way.
Sol, the 'Wilhelm Tell' black seedling had never been given the Quick Start.
Starting into it's third year, spring, was when it turned black, and it was very tiny as a three year old. I give it an A for survival.
