I like the first part of March cool shipping they are feathered out by May and can be outside and mine started to lay in mid July. I hatched in April, May, June and July the last ones hatched are getting big now the ones hatched in April and May are laying up a storm and it looks like the June hatches will begin to lay in December. I'm going to be hatching from my own breeding program in January so soon I will know what gives me the best chicks size and development wise but for laying only I would say from March thru May for keeping the cost down on brooding I would go later I loved my summer hatches needed very little lights for warmth.