After about 4 weeks, Cornish Cross chickens are ready for the move outside. Cornish Crosses are very fast growers. Most other breeds take more like 5-6 weeks to reach this stage. What you want to look for is feather growth. Remember, the reason chicks are placed in a brooder is because they can’t control their body heat and need to be kept warm. Feathers provide the insulation for them to do this on their own. So as soon as your chickens look like the fine specimen on the right, they’re ready for the great outdoors!
(Note: actually, because of the weather… early May was unusually frigid this year… we put off the move about a week to a week and a half. The chickens in the picture are actually a little older than normal.)