Purple Cone Flowers turning black and wilting Home › Forums › Flower-Garden Questions › Annuals and Perennials › Purple Cone Flowers turning black and wilting This topic contains 0 replies, has 1 voice, and was last updated by Anonymous 8 years, 7 months ago. Viewing 1 post (of 1 total) Author Posts September 13, 2008 at 5:48 pm #28446 Anonymous I had the same problem with almost all my coneflowers this year (all varieties), outside of Hudson in zone 5. Completely black, and early. I attributed it to too much rain, but would love any other insights. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.