Yeah I probably wasn't clear enough there - it grows perfectly fine in British weather, so don't water it unless there's a drought, the rain will do the job fine. Unless you have some kind of particularly bad soil, it should be as simple as planting bulbs and leaving them there until harvest.
I asked my dad about mulching and he said "I dunno, I always just stuck 'em in the ground", so I'm gonna say probably not necessary - when he grew it on the allotment we never lacked for garlic.