The plant protection devices mentioned should work (any physical barrier should do the trick, and a bit of vicks vapour rub or equivalent rubbed on the stakes around your hop crop should deter dogs and possums).
However something that has not been answered is.. why is the dog digging up the newly planted hops? Why didn't the dog previously dig them up at your old house?
I find there are two common reasons for dogs digging up newly planted plants.
The first is, did you use blood and bone or some other organic fertiliser when you planted? This makes dogs crazy.. they can smell the blood & bone so they assume that you've buried a bone in there, it's just a matter of digging around until they find it. So maybe try using a pelletised fertiliser if this becomes a big problem.
The second is, was the dog watching you as you were planting? Dogs are smart, they know that the only reason to dig a hole is to bury a bone. They don't get the whole gardening thing.. particularly when planting rhizomes where you dig a hole, and fill it in with nothing showing on the surface. So they watch you digging around in the garden, assume you're hiding your meat/bone stash and as soon as you're out of site they'll do their best to find your buried treasure.
So in a nutshell, don't let your dogs watch you when you're planting, and be mindful that organic/blood based fertilisers smell like a buffet to dogs.
Cheers,
Al
