Topic: Black Fly treatment

[gwencross]

I am thinking of trying dilute washing up liquid on my broad beans----ie the black fly. Has any one tried this and with what results? Any better ideas using kitchen stuff?

thanks   GG

[Multiveg]

The washing up liquid (or soft soap) spray for black fly should work. Remember to spray either early morning or in the evening so to avoid scorching the plant. Also, you should, if you haven't already, pinch out the growing point tops of the broad beans. If you have ants "milking" the blackfly, try putting some jam (what Bob Flowerdew does!) which the ants will then take (as they have a sweet tooth - do ants have teeth??). The ants would otherwise protect the blackfly from predators.

[Chaz Hunter]

I was just going to post the same topic!! I've just spotted blackfly on my Broad Beans as well as on the growing tips of my redcurrants; I know the washing up liquid works on greenfly so I'll have a go at the black ones tomorrow, don't want to use insecticide so lets hope it works ;)

[ina]

Does washing up liquid actually have soap in it or is a detergent? I'm not sure what all is in washing up liquid so I'd rather stick with real soap.

I always use soft soap, the green/gold stuff that comes in a little tub and put a little bit of spirit with it. It works but you have to repeat the treatment after two or three days!

How much do I use? About two table spoons of soft soap and one tablespoon of spirit in a 1 liter spray bottle I think.
Actually I do a glob of soap with my hand and a small glurk of spirit, mix well with warm water and fill the spray bottle with it.

[Mrs Ava]

Ina, I am glad to see that you are as scientific as me!  ;)

I seem to have got away with no blackfly so far this year (touching wood, spitting and whistling, crossing fingers and toes) so haven't yet pinched the tops out.  Are there any benefits for pinching the tops, like do they branch and produce more beans?

[Multiveg]

I think pinching out concentrates the bean's resources on the pods.... Beans perhaps then are slightly earlier.

[gwencross]

I like the idea of adding spirit to the mixture. Is this Meth or white  or even alcoholic? Perhaps that would rule out the need for any thing else and make the beans taste interesting.
Does anyone know if there are nasties in the washing up liquid? I really dont want to spend out for soft soap if I can help it.
Incidentally. A lovely drop of rain at the moment.
thanks   Gwen

[philcooper]

Washing up liquid IS detergent and should not be used - it will harm the plants.

Use either soft soap or soap flakes with a touch of washing soda

I was told that the aphids have a waxy skin and the soap disolves it - as they breathe through their skin, they suffocate

I just thought you'd like to know that!

Either of the soapy solution work well but even they can harm some plants (more than one application scorches fuchsia leaves) so try them out carefully on anything decorative

[derbex]

Just to back up Phil -I used Ecover washing up liquid diluted as a spray last year (as I couldn't find soft soap) and it killed the Nasturtiums I sprayed it on, and very nearly killed the peppers (they dropped most of their leaves).

Jeremy

[kenkew]

Isn't 'Derris' liquid a natural product? It's for use on plants including food plants.

[philcooper]

Derris is a plant based product which, like soft soap, has "qualified approval" from the HDRA.

That means it can be used when moving from a conventional regime to fully organic or in emergencies, but should not form part of the normal way of working in an organic garden.

Derris is very poisonous stuff and kills a large number of insects so should be used in the evenings when the beneficials has gone yo beddy bies - it also is lethal to fish, so don't use it near ponds

Phil

[aquilegia]

I tried using washing up liquid spray against greenfly on my osteos that were overwintering on the kitchen window sill. I had four plants, now I have none. They all withered and died but the greenfly didn't.

[gilgamesh]

Soft soap works much better than washing up liquid - as it dries, it seals up the spiracles & suffocates the aphids. W-u-l helps to dislodge them, but in my experience it's not much better than spraying with plain water.

[philcooper]

Why risk using detergent when soap flakes are sitting on the shelves in places like Tesco's??

Ecover is enviro friendly as it breaks down in the sewage system but it certainly ain't plant friendly!!!

[Multiveg]

If there aren't too many of the blighters - finger & fumb do the job

[john_miller]

This gives the explaination that concurs with what I have always been told:
 http://chattanoogarose.org/Soaps%20and%20Detergents.htm
As someone who has managed to defoliate both Fuchsias and peppers (among others) with both dishwashing liquid and 'Safer's' soap (a commercially avilable insecticidal soap over here) I am well aware of the similar effects of both. The way I have overcome this is to spray late in the evening to avoid the phytotoxicity (which also works best for whitefly as the adults don't fly off so promptly at this time) problems, or to immediately spray the plants with pure water to dilute the liquid to such an extent it no longer reacts with the leaf waxes.

[philcooper]

Thanks for that John.

So my information about soaps suffocating the little blighters is possibly true.

A couple of points though,

1. the brands of soaps are presumably the US flavour (flavor ;D) and the UK/European versions may be differently formulated so may have better (or worse) effects on both insects and plants.
2. All soaps, but detergents to a greater extent, effect the leaves of plants (especially, as we both have experienced, fuchsias)

[pbjohnson]

Two rather silly questions:
1. What name do soap flakes go under in the supermarket (simply soap flakes?) and where are they sold (with washing up liquid, stuff for washing machines ... sorry showing my ignorance here)
2. I've got quite a bad infestation on my broad beans.  The beans have started to form but the plants are trying to throw out more flowers from the top ... if I nip out the tops I'll be nipping out all the new flowers and reduce my yield.  So what if I do nothing?  Do the blackfly actually attack the bean pods aswell?

Please be gentle!

[philcooper]

1. Soap flakes - in packets like washing powder, and probably somewhere near them (they are in my Tesco)

2. You can reduce them considerably by squashing them with fingers and thumb (a bit messy if there are lots) or spraying with plain water will knock (most of) them off. In a bad infestation they will cover the young bean as well.

Phil

[philcooper]

The recipe is 2oz of flakes disolved in a small amount of hot water then made up to 2galls with cold water (+2oz of washing soda - not caustic soda - so that's a small amount to 50mils (enough to make it very soapy) add one crystal of washing soda, if you have it, (again, from Tesco, or a hardware shop) and use straight away as it tends to solidify if you leave it.

I know cos I've tried it

According to John's website slices from a bar of soap should also work, but I haven't tried that and don't know of anyone that has

Phil

I now normally use soft soap - a tub cost me ~£2.50 from the HDRA shop at Ryton and I've only used half of it in 3 years!!!!

2 heaped teaspoons to a small amount of warm water then toip up to 1litre with cold