Devon,
United Kingdom 
After years of planting Iris Reticulata with no problems from squirrels, I found this winter's pot surrounded by empty bulb skins! Well I hope s/he needed the food because my display will be sadly depleted though still lovely, I hope.
I read somewhere that grated soap deters squirrels but I can't imagine that it does the compost any good. Are there any tried and tested ways to stop them digging up bulbs? I put net on the pot after the discovery, so I assume that's one way.
30 Dec, 2012
Answers
I do have problems with squirrels and i do put chicken wire an inch under the soil. seems to work ok. I have found mice also dig them up, a wood mouse decimated over 200 crocus corms in the greenhouse last year. so that may be a culprit too.
30 Dec, 2012
I have problems with squirrels too and put upturned hanging baskets over my pots, pegged down with bent wire.
31 Dec, 2012
Thankyou for the replies. There are mice nesting in the shed so yes, maybe I'm wrong in assuming it's a squirrel. The chicken wire solution seems a good one and the hanging basket is even easier!
31 Dec, 2012
What about some chicken wire rather than nets and if you didn't want to see it, it could easily be hidden under the surface.
I don't have problems with squirrels so am only guessing :)
30 Dec, 2012