I won't leave any bulbs outside overwinter as I've read that the hardier types can handle down to -20 C (we just had a couple of weeks of -45 C weather). The refridgerator was cool enough to induce blooming without killing any bulbs.
My summers (outdoor) are not hot for long and I think we'd be lucky to get 100 frost free days. The only downside to outdoor growing over the summer was that leaves were more beat up looking (wind, sunburn and bug damage). They do need a fair bit of water while growing, I always find my media to be dry when the plants are getting enough light (my media is a mix of coir, fine bark, charcoal and gravel - with good drainage).