[mjg000]

I have lost 2 lots of BB's to Blackfly this year, first were sown in February and looked lush and gorgeous, lots of flowers and sturdy until the Blackfly descended in early May, soapy sprayed, jet-washed and squished until the blackfly got the better of them in the week of 22nd June and I dug them up.  The others, planted in April were also doing well but succumbed in Mid June and I have finally chopped them down this week.  Not a single bean was eaten from them.  No ladybirds until the last week or so.  I have never had such a disaster with BBs.  In terms of when Blackfly strike, you can't set a clock by it, I have had it early and late ( first sighting in mid July in 2012 ) but have never lost a whole crop to it.  I will be trying Wizard beans next Autumn and see how resilient they prove to be.  I am also thinking of maybe using dense scaffolding net once the flowers have set.

[compostqueen]

I grow broad beans in a well manured bed and then let the bed do its own thing and allow the weeds to spring up around the beans. As long as the soil is fertile you'll get a goodly crop of beans.  I pinch out the tops as soon as possible. 

This was discussed on GW some while ago when Sarah Raven visited Riverford Organics and asked them how they grew vast quantities of beans without recourse to sprays. That was the answer, so I tried and it works. I assume the pests can't find the beans cos of the weeds and fly somewhere else     

I suppose the bottom line is about monoculture. Things don't grow in serried ranks, with bare soil around them, in the wild.

[LottyLouis]

Now then, Compost Queen - that is a seriously interesting idea. I feel an experiment coming on!   

[compostqueen]

She who dares wins 

[ptarmigan]

My over wintered broad beans have given a fantastic crop, despite being blown over in the gales in June and chocolate spot. Spring sown ones no sign of blckfly yet, but I'll pinch out the tops.

[sunshineband]

Somebody (Surbie, Newshoot, Sunshineband maybe?) recently remarked that their Wizard Beans had lots of blackfly but the harvest wasn't affected. They might be worth giving a go. Wizard are also apparently very hardy, so would be good for autumn sowing.

My Wizards beans were heavily infested with black fly but persistence, plus what seems to be a sudden decline in numbers all over the place, has paid off and the plants and pods are virtually free of them now.

Taking the tips out of plants when they have set all of their flowers also removed the bit the blackfly like the best. You can eat these tips too 

[missmoneypenny]

Maybe I'm just bitter and twisted, I love HFW and all, but really???http://chat.allotment-garden.org/Smileys/green/huh.gif I sowed my beans in soil enriched with lovingly rotted kitchen manure back in the autumn (a pea trench). That didn't deter the blackfly. Maybe I needed a few more weeds there.

[missmoneypenny]

Sorry Compost Queen I see it was Riverford Organics, not HFWs River Cottage.

[dugless]

I always grow two lots 1 in Late October and the other at the end of February, I pinch out the tops  as soon as they get to 18" high. No black fly as they like the fresh tender shoots at the top. works for me.

[Steveharford]

Pinch out the tops and spray with bug clear. No point messing about.

[New shoot]

Those of a nervous disposition, look away now.  These are my Wizard beans in all their awfulness    The crop has been great and to recap, these were direct sown last autumn, never weeded, watered or bug sprayed.  They have no supports and apart from an occasional handful of chicken manure pellets, I have left them to their own devices.



I have lost some of the very late set pods as they were too small to withstand the onslaught, but here is the reason I didn't spray.  This is the ladybird population on one small piece of one plant.  I am ignoring the beans now and growing the ladybirds, so they can disperse all round my plot   

Oh forgot to mention, the beans were grown from my own saved seed, so it really was a crop for nothing in terms of money, time or effort 

[LottyLouis]

Good gracious - good for you - what a result. Nature has a way of getting on with it - I think, sometimes, (actually a lot!) that we interfere too much.   

[Steveharford]

That is good to see. I must say any autumn sown beans i have grown are usually harvested before black fly take a hold but I gave up growing them as the mice had 50 percent of them. I do have a load of wizard which I bought for green manure, though, so I might give them a try this time.

[miggs]

I will be spraying mine in the morning after finding quite a few plants infested with the little blighters. It's the first time I have grown them so I don't want to loose them.

[dugless]

I have just found the blighters on my runner beans so out came the spry gun.