I've never grown outdoors, but I would say in late February, start your seeds and put them in a window that gets lots of sunlight throughout the day. that way you'll have a plant that's getting mature, so when you replant it it will be strong and wanting more soil to grow in. so the question is when to replant outside. well that's up to nature, I would look/think back over the years and see when the last cold days hit under 60s at night and go one week later. if I had to guess I'd say it's around mid to late march. but don't worry because you'll have somewhat mature plants getting planted so even if your a little late it will be ok.