Kitchen Garden Forum

There seems to be a 'glut' of greenfly around already this year and some of my Lupins and Chrysanthemum plants have been attacked....the Lupins especially.

I was talking to a gentleman I met the other day who deals with agricultural chemicals and he made the following statement....

''Many of the pesticides contain soap...my old Grandfather used to spray his crops with a solution of carbolic soap and never suffered from Blackfly or Greenfly''.
Now when I cast my mind back carbolic soap was used (in the old days) a great deal in the home and in hospitals but seems to have gone out of favour so much so not many shops sell it these days.
I have discovered on the internet that there is a Carbolic Soap Company still producing and selling it.
My question is..... has anyone any recent experience of using carbolic soap solutions in the garden/allotment, if so what are the results?

I have no doupt your gentleman aquaintance is correct. Quite a few 'Old gardener's tales, were based on fact. A lot were arrived at through a lack of spare cash to keep the garden Centres growing 'like Topsy'.

Cheers, Tony.

Not carbolic but did put a tiny drop of Fairy washing up liquid in a sprayer of water and spritzed my olive tree (more like a very small bush) last year when it was covered in teeny black flies and sage that was crawling with aphids.

Worked a treat.

Spraying with soap solution is supposed to damage the protective greasy coating that the flies have but Alan Titchmarsh reckons all you get is very clean aphids.

Happily, I have a good population of hungry ladybirds haven't noticed any blackfly/ greenfly,

solway cropper wrote:Spraying with soap solution is supposed to damage the protective greasy coating that the flies have but Alan Titchmarsh reckons all you get is very clean aphids.

I don't know about the protective greasy layer, but it does block up their respiratory apparatus, their spiracles, effectively suffocating them. It does work, but it needs to be regularly applied, and applied directly to the pests, to be effective. There are soap-based insecticides on the market which are formulated to be a bit more effective than washing-up liquid — I've always had good results with Savona. But only through persistence.

Interesting... Thank you all..

I wonder if the smell of the carbolic makes the concoction a bit more potent to the pests than ordinary soap solution?

There's certainly lots of ladybirds.