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Blackfly problems

TriciaBTriciaB Posts: 36
I'd be interested to know whether people are finding more problems with blackfly than usual this year. All our beans (climbing, French and runner) are covered and some plants have died. I have been spraying with washing-up liquid in water as recommended but it's a losing battle. We've never had a problem on this scale before.


  • Mine have been much worse than normal this year but the ladybirds and their larvae seem to be just about keeping up with them.
  • nick615nick615 Posts: 1,366
    There are some who fear the method I use, TriciaB, which is to boil rhubarb leaves, strain off the liquid when cool, fill a household spray and spray the aphids.  The fear is in case any of the fluid, which is poisonous, remains when the beans are picked, but I can only say we haven't suffered from it and, if unsure, just wash before eating.
  • YviestevieYviestevie Posts: 7,045
    I've had loads this year but fortunately we had a load of wasps that descended and ate the lot over a period of 2 days.  It was fascinating to watch.
    Hi from Kingswinford in the West Midlands
  • cornellycornelly Posts: 970
    Soapy water cleared ours, mind I was ready for them and caught when just a few,  kept on top of it, clear now.
  • REMF33REMF33 Posts: 696
    edited July 2020
    Yes. I am having terribile problems. I always get them on my philadelphus, but this year on dwarf cherries, marigolds, nasturtiums, French beans, strawberries, cornflowers, sunflowers...
    I have been using washing up liquid solution, castile soap and neem oil soution, RHS bug and mildew spray. I think the problem is just too big. 
    I have a lot of ladybirds, but I think they arrived too lat, and I alwasy seem to find them on other plants (perhaps they are eating other things.) I have a lot of greenfly too, especially on the sweetpeas (which also have powdery mildew.)
  • FairygirlFairygirl Posts: 52,124
    Never have them.
    I get the odd greenfly - mainly with new growth on clems and sweet peas, but the birds get them. 
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • PurpleRosePurpleRose Posts: 538

    I think these past 2 years have been bad for black fly. Out Elderflower Tree is covered in them. I blast the affected parts with a hose pipe.
  • TenNTenN Posts: 131
    Squeeze most of but leave some for other beasts.
  • TriciaBTriciaB Posts: 36
    Thanks to all for your comments. The problem is such that soapy water and hosing has failed. I shall have to hope for wasps (hmmm be careful what you wish for!) or boil up some rhubarb leaves. I am wondering if it is too late to plant some more French beans if I can find somewhere to put them. We have put brassicas in most of our space available and the netting over them appears successful at the moment. There are a lot of frustrated cabbage white butterflies hovering about though. They say that in gardening you always win some and lose some. The experimental sweetcorn is looking good but the Autumn raspberries which last year were brilliant are hardly doing anything. We wish we knew why!
  • The blackfly defeated the runner beans and we have had a very poor crop. We are still hoping for a few more as there are still flowers. I would appreciate opinions on whether it would be advisable to put the plants on the compost heap when they have finished growing and producing. I would hate to push the problem into another growing season.
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