I've not yet hatched my own eggs - I'm building the incubator now, but I had also planned to stuff a bunch of eggs under a broody hen in the spring. I've had 3 of my hens go broody in the past 6 weeks. My first thought is that it will be too cold to let the hen brood some chicks (so far it hasn't been). So as far as brooding hens go - can they successfully hatch & raise chicks if it is in the 20's 30's & 40's? By the way - the flock is totally free range - I only lock them up when the kids grandparents bring over the killer yorkies. The broodies have been Aracauna & Buff Orp.