I have 12 chickens that are 6 and a half weeks old. They are pretty well feathered out. They have been outside in a coop for 2 and a half weeks with a heat lamp. The coop is almost completely open on the south side (except for a strip of nest boxes 18" off the ground). The coop does not have a floor, so they are running around in the grass. I have a large shallow plastic tub in there with pine shavings that they sleep in. One edge of it is located under a 250w heat lamp that is approx 20-24 inches above the ground. Over the past week they have spent several days without the heat lamp during the day, only used once the sun went down. The daytime temps ranged from upper 30s to upper 60s during this time. I unplugged the lamp yesterday morning - temps in mid 50s. Last night I did not turn the lamp back on because the low was 50 degrees, so they have not had the heat lamp since yesterday morning. Tonight it is supposed to drop down to 34 degrees.... Do you think it's okay to leave them without the heat lamp tonight? Then tomorrow night is supposed to get down to 19.....so I'm thinking I should turn it on for tomorrow night. I know once full grown, they will be perfectly fine at these temps. I'm just concerned about them not being acclimated yet to the cold without a heat source. Of course there are 12 of them, so they sleep huddled together for the most part and will help keep each other warm. Thanks for any advice!