Two days ago, I noticed Blackfly on my 12" high BB's, my mate (another allotment holder) correctly told me to use soapy water to wash them off.
I poured in some Fairy liquid and topped up the plastic sprayer with cold water and began spraying.
To my horror the leaves turned black virtually in front of me, now all I have left is the stalks with damaged leaves and some small undamaged leaves at the top (so they are still growing).
I had put too much detergent into the mix, so I've planted somemore just in case I don't get a crop from the damaged ones.
Just to let other people know what can happen, this is my first attempt at growing them. I've since read that I should have used a Tea spoon of detergent to two litres of water.
We all do stupid things. I managed to leave a set of plastic bottle on some dwarf beans during the day, I put them on when I planted them out to protect them from slugs and forgot to take them off the next morning. Come the afternoon they got cooked. They are looking a bit sad now.
That's your reward for using unlicenced sprays.
If you are looking for an organic remedy for black fly infestation then you need a soft soap solution. (Washing up liquid is a detergent and contains chemicals.) You can buy soft soap (pure soap) in garden centres.
G x
Quote from: Georgie on June 02, 2009, 22:54:25
If you are looking for an organic remedy for black fly infestation then you need a soft soap solution. (Washing up liquid is a detergent and contains chemicals.) You can buy soft soap (pure soap) in garden centres.
G x
Thanks for the info Georgie, I hadn't realised there was such a product !
Can you use soap flakes? I got some organic ones from John Lewis to put in the rhubarb spray.
Janet
Quote from: Georgie on June 02, 2009, 22:54:25
If you are looking for an organic remedy for black fly infestation then you need a soft soap solution. (Washing up liquid is a detergent and contains chemicals.) You can buy soft soap (pure soap) in garden centres.
G x
Yes, thanks for that. I'll get some for the next time I have an infestation.
plant some nasturtiums too - the blackfly flock to them and leave the beans alone! (I always feel sorry for the nasturtiums though!)
Last year I had exactly the same problem and did exactly the same thing with the same results although they still grew but smothered with blackfly and made picking the few beans that I had impossible. This year I pinched out the tips really early, when I saw the first flowers budding, and I have absolutely no blackfly and tons of pods with swelling beans in them. Some pods are about 4 inches long already. Before this year I had no idea about pinching out and I really worried about when to do it. Some people say when the flowers bud, some when flowers open and others when pods show. If I hadn't done it early I think that maybe my beans would have been smothered in blackfly again, so my tip is pinch out tips and maybe you won't have to use soap solution this time round.
I prefer to use the five sets of flowers routine as this caters for early or late seasons.
This is an extract from my website;
Week 25; Remove the top three inches of the growing tip from each plant to deter 'blackfly'.
An alternative time to do this is after five sets of flowers have set.
These black aphids overwinter on shrubs and migrate to beans in spring.
If the above treatments fail to prevent their presence, treat them as soon as they are seen.
For organic gardeners; spray insecticides based on derris, fatty acids, plant and fish oil or pyrethrum to the underside of foliage.
If this fails, consider using a synthetic insecticide containing bifenthrin.
Muddylou, another newbie here, and I did exactly the same thing! I used waaaaaay too much washing up liquid in my spray and caused a lot of burn. :/ Oh well, live and learn! I've pinched off all the tops now, but unfortunately, the blackfly have got quite established, so there are still a lot. The good news is that I only intensively sprayed some of the plants, others are fine. But will be very cautious and use a much, much weaker solution next time. :) I'll follow TeeGee's advice in future.
Quote from: 1066 on June 02, 2009, 23:21:44
Quote from: Georgie on June 02, 2009, 22:54:25
If you are looking for an organic remedy for black fly infestation then you need a soft soap solution. (Washing up liquid is a detergent and contains chemicals.) You can buy soft soap (pure soap) in garden centres.
G x
Thanks for the info Georgie, I hadn't realised there was such a product !
You're welcome. :)
Quote from: grannyjanny on June 03, 2009, 07:04:01
Can you use soap flakes? I got some organic ones from John Lewis to put in the rhubarb spray.
Janet
Yes you can if they are pure soap - should say so on the packet. :)
G x
Will keep an eye out for this, mine are still small just now, was late putting them in I think. Checked tonight and they are okay.
Thanks for the warning !
My friend picks off the top leaves of broad beans and uses them in salads. Before the black fly attack of course. I have not tried them yet, but will give them a go.
I honestly do not care about this 'organic' rubbish. If I get bugs. I spray with the cheapest I can get. Soap and water is far better for bugs than anything else.
It is hard to find pure soap these days.
Thanks for all your replies and the information within them, but they have led to a bit more confusion on my part.
Firstly how do I "pinch out" things?
Secondly my Beans are only one foot high and don't have any flowers on them but still had black fly. Should I have left the insects there until the beans flowered and then pinched out.
I may just pull up these beans as I've planted more, doesn't seem worth persevering with these If I'm not going to get a crop.
I appreciate any replies but remember, your talking to a bit of an idiot on these matters. ;)
Quote from: muddylou on June 03, 2009, 22:12:35
I appreciate any replies but remember, your talking to a bit of an idiot on these matters. ;)
Muddy in my book 'idiots' are those who think they know it all not amateurs who are looking to learn. No question is daft. I'm not very experienced in growing broadies so I'll leave it up to others but please don't get discouraged. :)
G x
Interestingly, I'm growing crimson flowered braod beans and they seem to have escaped having blackfly altogether! There is blackfly on my foxgloves, but I just wash them off with the thinnest jet of plain water from my hand sprayer. Doing that a few days on the trot and they have not yet come back....
A long time ago ironmonger shops would sell a little wire mesh cage with a handle on it that we put all the scraps of hand soap in it, close it and whisk in water to make a soapy mix then spray on the beans to kill the black-fly, but you had to watch out for the doodle bugs. ;D
There is a totally organic solution which works fairly well!
If you know where there are some elderflower bushes - pick a few small branches and place these into the ground amongst your broadbeans - works pretty well for me!
Old Bird ;D
Quote from: muddylou on June 03, 2009, 22:12:35
Thanks for all your replies and the information within them, but they have led to a bit more confusion on my part.
Firstly how do I "pinch out" things?
Hi, this is my 3rd year of growing them, so no expert, but I have learnt so much from this forum! If you look at the top of the broad bean plant you will see a few small leaves almost bunched together, they'll be a couple of inches big. You literally pull or pinch these off.
Hope this helps
1066
When to pinch out?
I wait until I see the first signs of blackfly, then breakout all the top shoots. By waiting for the first signs you get the most bean pods set before pinching out.
Why do you all worry so much about a few little flies?
They come. They get eaten.. The beans are still there for me. what's the problem?
Depends how bad they are. They're no problem for Aquadulce Claudia, but when I tried Grando Violetto, which apparently has no resistance at all, they were eaten alive. I wouldn't try that one again!
Thanks everyone, I now know how to "pinch out" and thanks for all the other helpful info posted. :)
never mind this organic rubbish haldf of them say that and then use slug pellets. Grab a bug gun and nail em.