Hi there - looking for an answer. Planted the white echinacea and the leaves went black. The plant wasn't too healthy to start with, but wondered if my new amended soil was just a trifle too rich. I did ask the guy who brought the rotted manure and top soil (all mixed in) whether the manure was really aged and it certainly looked like it. Do you think the manure burnt the roots? No other shrub or plant seems to be affected - yet!! Thanks guys!