By Davrob
West Sussex,
United Kingdom 
my Sambucus has a sticky substance developed on the leaves and they are wilting. could this be caused by greenfly/blackfly activity and how do I treat it
3 Jul, 2017
Yes it could, but you should be able to see aphids actually on the plant. Scale insect can also cause sticky deposits. Otherwise, wilting leaves can be a sign of drought. If you see aphids or scale, buy a pesticide spray that treats for those.
3 Jul, 2017