Our Dahlia excelsa (present from David Hill) has had a real blackfly
attack.
I was walking past it this afternoon and saw twisted and 'sad' leaves and
then, further up this very tall Dahlia, several stems and leaves infested
with the critters. I don't remember it suffering like this before and as
there are loads of sparrows nesting in the eaves above it, I think the
ungrateful little devils better get to work!
Ray has sprayed it with an organic spray, so we will inspect again
tomorrow.
Is this a particularly bad year for blackfly in others' gardens?

--
Sacha
http://www.hillhousenursery.co.uk
South Devon
(remove weeds from address)
'We do not inherit the earth from our ancestors, we borrow it from our
children.'

I've just had a couple of stems with small clusters. I tend to use a
domestic Pyrethroid fly spray to spot treat these, not worth mixing
for 2 or 3 stems.

Sacha, your dahlia is now in bud.
David Hill
Abacus Nurseries