At the supermarket in the cleaning aisle, I will ask Nanna the name cause I can't for the life of me remember, reminds me of Chlorophyl (Fernile or something)... but anyway, they HATE it, won't go within yards of it. You can put it around (liquid) your fence line etc and they won't go near it.
Dogs apparently aren't phased at all lol

Anyway, it is at the supermarket in the cleaning aisle, usually up high.