Black Fly making a meal of my beans

[MickSturbs]

Hello,

I have black fly munching my runner beans, I've used an organic spray which seemed to work immediately after the spraying (couple of days perhaps) although the little vermin reappear shortly afterwards.

The plants are doing well, plenty of flowers and a few beans coming through now. As there is lot foliage, I'm finding it difficult to reach the entire underside of the leaves with the small spray I've been using. It's also very expensive.

I am a complete novice; this is the first year I have grown. It seems my father's green fingered genes have taken a while to kick in for me. I would be very grateful of any tips members could give me, names of insecticides, method of spraying etc.

I'm really looking forward to picking my first basket of beans for the pot; I would hate to have these little pests ruin the crop.

My potatoes are also under attack, I'll post again for help on this one. Can you post pictures into a post?

Thanks very much for your assistance

Mark.

[Pat Kiewicz]

You will need to spray at least three times, at three day intervals to gain control of the black bean aphid (Aphis fabae). The organic spray you used (most probably) has no residual effect.

You might want to invest in a small pump sprayer and some insecticidal soap concentrate.

Don't use soap spray in the heat of the day; while insecticidal soaps are formulated for use on plants, they can still sometimes damage the foliage. Spray in early morning or in the evening. It may even be best to come back later and rinse the plants with plain water. (The soap spray acts on contact and will kill the aphids very quickly but will have no residual effect on the insects, so rinsing it off later won't help the pests, but can protect the plants from any possible harm.)

[MickSturbs]

Thanks Pat, much appreciated. I'll give it a go.

Thanks again.

Mark.

[Jake Newman]

Hi Mark,

this is my first post here so excuse me if your problem has already been dealt with. As it happens I have just blanched and frozen about 5lbs of French and runner beans as we've been eating them with every meal for a while, My beans were, in the early part of the season attacked very heavily with blackfly, apart from rubbing them off with my fingers I have found that collecting ladybirds and putting them in the bean bed has been a very successful control method. I won't use chemicals so it's natural or failure for me. My daughter has taken a very keen interest in what is the gardeners friend and informs me that a ladybird will eat 50 aphids a day so 20 ladybirds is a serious challenge to the aphid population.

Good luck with it and make a daily check on the blackfly population between yours and the ladybirds efforts you should be able to keep them sufficiently at bay.

Jake