Black fly, broad beans and washing up liquid

 As everyone has warned black fly have appeared on my broad beans. This
is the first year I've grown them. They've not even set any flowers yet
and several plants have colonies of black fly at the growing tip.

Knowing how useful washing up liquid is against aphids I've tried
spraying them with a relatively strong solution of washing up liquid in
full sunshine. After a few hours the results look promising, sort of.
The leaves below look like they've been splashed with black ink,
presumably from the black flies. They aren't moving any more. It will
probably be an ongoing process to spray them like this but if it works
it is a cheap and relatively organic way of dealing with the pest.

Anyone else tried this against black fly? Was it successful?

--
David in Normandy.   DavidinNormandy@yahoo.fr
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My old next door neighbour when we lived in Leicester was a real old country
woman and swore by this method :-))

Mike

--

...................................
It's nice to be important, but it's more important to be nice.
...................................

 Sorry, I'm not organic. Tried soapy water spray last year.....no effect.At
first sign this year, I used a bug spray. Complete success.
--
Pete C

 On Sun, 29 May 2011 20:35:59 +0200, David in Normandy


I've found that a  weak soap solution is good for blackfly but you
need to make it stronger for green- or white- fly and I've never been
happy about a strong solution since a treasured rose bush snuffed it
on me following a "treatment". I'm worried that with all the variety
of washing up liquid these days there's something in it that might be
damaging.

One organic solution (pardon the pun) available in the UK is a product
called SB Plant Invigorator. This was originally developed as a plant
feed thing but people found that it clobbered a lot of pests.
Certainly blackfly overnight and Toby Buckland says it kills lily
beetle as well. I'll see if I can find the compostition of it but
don't know if you can get it over there.

That said, here I have yet (this year) to see any black, white or
green flies. Scratches head strongly and gets splinter. This morning I
saw my first ant of the year. Must take myself to an optician,
methinks. It's just that, honestly, I haven't seen any of these bugs
(including ants) yet. No ant-hills in the lawn either, which I would
expect by now.

 Jake wrote:
<snip>


My rose cuttings were found by some greenfly, but paradoxically not the full
grown bushes a few yards away. Maybe the greenfly are developing a sense of
discernment and only going for the freshest young plants.


Ian