"sarah" wrote in message
. ..
Nick Maclaren wrote:

In article , "hillier"
writes:
| My runner and french beans are infested with blackfly. Soapy water
and
| derris liquid have not had a lot of success and although there are
lots
| of ladybirds this year, they can't cope either. Do I leave them
alone,
| pull all the plants up or can anyone sugest a different treatment,
| please.

I use Savona (horticultural soft soap), and it works. But you
have to soak the blackfly, so spraying by hand, close up and
under all leaves is essential. If you do that, and it failed,
try again, but perhaps with a slightly stronger solution. Also,
it works better if it is followed by some warm, dry weather, to
shrivel the beggars up.

I don't find Derris very effective.

That last is helpful, as it's all our local shop sells. Do you have a
local supplier of Savona, or do you buy online?



I managed to get a tub of generic soft soap from the local chemists - they
had to order it in though (I was surprised when I went there in the morning,
ordered it, and received a phone call in the afternoon of the same day to
say that it had arrived!)

Not particularly cheap at about £5 for a 500g tub, but it does last for
ages.

It was very, very effective against the blackfly on the broad beans, and
this year since the population was knocked back they haven't returned (so
far...).

--
Richard Sampson

email me at
richard at olifant d-ot co do-t uk