I dont wrap my bulb pots, nor cover them. I do put the pots close to the side of the shed or house wall though, neither of which are on the frosty side of the garden. That gives protection but allows the rain to get to the compost.
I do cover my pots with tied on pea netting though- squirrel prevention & also sometimes the blackbirds go rooting in the compost & disturb the top smaller bulbs. Net removed asap the shoots appear. Blackbirds can still uproot things, as can the 'b' squirrels. J.