At what tempurature should I move seedlings outside? (Chicago area)
Or does it matter as long as its not going to frost?
I think our official "frost free" date is May 15th, here by the lake. I think it's a week or so later out in the western suburbs. After that it should be OK to move things outdoors. Even though I live near the lake, I always wait until May 25th or so, just because I grew up in Michigan planting delicate things Memorial Day weekend. If you're in or near the city your biggest problem after that is going to be squirrels digging up your seedlings and burying things in their place. For some reason they find those little seedling trays irresistible.