Question From: NEW HAMPSHIRE
Q: I read your page on Cosmos problems. What I am seeing this year is not on your list of issues. We have very healthy looking plants with nice, thick stems and beautiful feathery leaves. The buds also look good but just as the flower open the stem below it shrivels and the flower droops over and eventually dies. Any ideas? I tried cutting open a stem to see if there was a borer but it seemed healthy. I am in southern New Hampshire. Thanks
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I'm pretty sure your cosmos have stem borers. The bad news is there is nothing to be done but destroy the plant. Google the Missouri Botanical Garden Stem Borers for a good explaination and method of control, which must be done before the damage appears. Best And Happy Yardening, Nancy
