A pockle is cat poo or indeed any animal poo found in your garden. The smaller and darker the poo, the more pocklier it is.
"Ooooh Betty, the cats done a pockle on the lawn again."
(var. poackle) swindle, cheat, hustle.
The wages were pretty shite, but the pockle was good.
Irvine Welsh - "A Smart Cunt"