Hello amber,
What you are describing is the characteristic shape of a weevil -
because of the pointed nose.
I am thinking that this isn't a vine weevil. There are many weevils
and a number are pests - boring into grains of wheat, leaf eaters etc.
Here is a link that has a pic of a vine weevil on it.
http://www.rhs.org.uk/advice/profile...vineweevil.asp
the picture of the weevil is not the best but note the dark colour and
the small spots in a line.

Am sorry but I am not an entamologist and cant identify it. You say
they are on the mentioned plants, is there any damage bening done to
the tops of the plants? (for it is the grubs that normally damage
roots)
Regards
Cliff
Bawtry, Doncaster, South Yorkshire