apparently with a gun , a dog or a ferret

It's certainly not easy! There is plenty of information on the net about plants they (allegedly) don't choose to eat, but other than building those up in your garden and wire fencing buried deep and turned in underground towards the garden are the only things I know of, apart from the more drastic solutions......

Dried chilli flakes!!. We have a rabbit problem and when they decimated my alpine trough (looked like a battlefield) Chilli powder was suggested as it deters squirrels on nuts....it has worked amazingly well, the flakes are best(cheapest from the ethnic aisle in the shop) you need to replace them only after heavy rain, the pests did have a couple of goes but soon left it alone.....good luck!