On 08/11/2020 12:37, The Natural Philosopher wrote:
On 08/11/2020 12:14, Spike wrote:

Dilute bleach, especially with added washing-up liquid, will kill black
spot

No, it wont. Or at least it wont remove the staining.

BTDTGTTS

I get an old trigger-pack - mostly the tops are a sort of bayonet
fitting and are easily replaced once removed - I flush it out then add 1
part of thick bleach to 4 parts of water and two drops of washing-up
liquid; then replace the top and repeatedly invert to mix the contents.

I've used this to remove several hundred black spot (and brown spot)
growths from both my and my neighbours footpaths, and there's no sign
they were ever there, and they have never returned. I treated them every
couple of weeks for three or four treatments.

I think this kills white spot too, but they seem never to fade away;
they are best zapped while very small and this seems to stop them
getting any bigger.


--
Spike