Found this the other night,
Soot from coal fires put on the garden in the autumn will deter black slugs from eating your potatoes next year.
Yes, I heard that too. Earlier this year I used soot on my potato bed and I've had minimal slug damage. The soot is dumped by a cleaning firm behind the hut of my local horticultural society for everyone to help themselves. However, I've decided not to use it again because there is no way I can know what was burnt in the fires and what chemicals the soot may or may not contain...
I do use wood ashes (as a fertiliser and to raise the PH of thre soil slightly), but the ashes are from my own fire so I know exactly what it's made of!
Wood ash ia apparently great for alliums.
I got a bag of soot prior to xmas adn told it was good on the plot. Is it too late to put down now where spuds are gonna go??
I'm with Dandelion ,not many coal fires out there now days ,we get soot left by a cleaning firm but you never get two lots that look the same and some time's it just don't smell right, :-\ god knows what's in it. :o
I have about 12 bags of it years old I think, smells good and I read the other day that it deters carrot root fly if spread between the rows, so i am guessing it should do the same for cabbage root fly, going to give it a go anyway. I think I remember my Father telling me that you do not have to use to much of it but forgot now what "to much" is.
my dad puts it in the bottom of the row then puts the seed potato on top of the soot, dont use fresh soot as it burns, wait about a year then its ready. stops the black slugs.