Spuds and manure.

Ok so someone said I will probably need to add nutrients back into my soon to be potato patch due to the huge heathers I am evicting.

My question is if I use manure how well rotted does it have to be if at all?

Many thanks.

So any thing that doesn't smell will be ok? I have a friend with horses looks like I may need to pay her a visit :-) How much are you supposed to put down? Is there any rule to it?

Many thanks x

Thank you