By Rosedaisy
Hertfordshire,
United Kingdom 
I planted an Eupatorium rugosum in April this year and within a few weeks the leaves started to droop. I noticed some flies on the leaves and promptly cut the stem off. The plant recovered and appeared to be doing well. Over a period of weeks one stem at a time has drooped and died. If I continue I will have nothing left although new growth is appearing. Can you please help me?
23 Aug, 2011
Answers
Did you plant it any deeper than it was originally? Often, having soil piled around the lower stems will cause them to die one at a time.
24 Aug, 2011
Rather than cutting the stems off just spray with an insecticide, as you say, if you keep this up you'll have no plant left.
As the plant was only planted in April you need to water it copiously in the first year of growth and it'll droop and be susceptible to aphids as and when it dries out.
23 Aug, 2011