I would really like some advice I have 5 hens happily outside in a chicken coop. They have a heating lamp because some of them still have some rubbed raw spots from overmating before I sold off my rooster. I have 5 pullets in the garage in a brooder. They are now almost 7 weeks old and to my eye look fully feathered. There are 4 astalorp/sussex pullets and 1 wyandotte/sussex pullet. Where I am in Colorado it is above freezing in the day, and below freezing at night. So here is my question, assuming the weather neither gets warmer or colder and with the assumption that not only will I leave the current heat lamp in the coop, but I will also add the second one that has been keeping the brooder warm on the other end of the coop- how many weeks should I wait until I put my pullets in the chicken coop and let them into the run?