Hi
Pick them off they will cause havoc to your plants.(please dont use
chemicals though).
The black stuff IS caterpillar droppings.
I had an infestation of these on my calendula one year....devastation!!!!!
Roy

"Kostas Kavoussanakis" wrote in message
q.np.hx...
Hi,

I was wondering why the new leaves of my giant hollyhocks were full of
holes. I just noticed large (5cm) gray, green and brown caterpillars
on them. Any idea what they are? Should I leave them to continue their
deeds or will even the hollyhocks eventually succumb? I have never
seen the hollyhocks flower (seedlings transplanted last September;
leaves then munched away by earwigs).

I also noticed small black balls on the same leaves; poo or eggs? Or
just "dirt"?

TIA,
Kostas