I have a one or two year old echinacea plant with one flower bud about to open, but absolutely no leaf growth at the bottom of the plant. It is planted in full sun. What is the problem, and how can I stimulate the plant to develop a lush growth of leaves, creating a full, sturdy, more prolific plant? I will deadhead after the flower fades. Does this plant need fertilizer, or organic material - I thought that echinaceas liked dry, not so rich soil!