They survived just fine...

[Ridgerunner]

They can handle a lot more than many people realize, but they can also get into trouble. There are a lot of different things that come into play as far as brooder temperatures go. Number of chicks, breed, size of chicks, their diet, type of bedding, how draft free is it actually, and many other factors. Nobody knows what all of your actual conditions are. The guidelines given on here are intended to keep practically everybody out of serious trouble practically all the time, assuming they are sort of following standard practices.

Since we all have different conditions and circumstances, following the guidelines exactly does not absolutely guarantee success. Not following them exactly certainly does not guarantee failure. The guidelines are intended to improve your odds of success, not guarantee anything, but they are slanted to help people be on the very safe side. For most of us they are overkill. But for a rookie starting out, it is nice to have very safe guidelines to go by.

In most cases, chicks five weeks old are fully feathered out, so they can handle pretty cold conditions. Exactly how cold depends on whether they really are fully fearthered, how draft free the coop actually is, whether or not they have been acclimated to cooler temperatures, how many there are, and who knows what other factors.

About the most miserable I've ever been from the cold was when I flew from 90 degree weather to where there was snow and ice on the ground with a wind, although I was properly dressed. A lot of people don't appreciate the importance of acclimating the chicks. To me, that is a huge advantage of brooding out of the house in a brooder big enough that one corner can stay warm but the rest can cool off a lot. I'm offering this as an example of how we have different conditions. The guidelines say they are normally fully feathered at five weeks and can handle the cold, but if you have not acclimated them and the temperatures are pretty severe, and your coop conditions are not reasonable as far as draft protection, even the guildlines may not work perfectly.

Or you get the flip side of this. I had a broody take her 2 week old chicks to the roosts with night-time temperatures in the lower 70's. Not all could crowd under her to stay warm. By the guidelines, they should have bee in trouble, but they all made it fine.

Until you get experience, I suggest trying to follow the guidelines. As you gain experience, you will better understand what you actually need to do in your specific circumstances.

 

[Ridgerunner]

1. When can a young chicken be put outside in the fall/winter? We live 40 miles East of Sacramento, so not too far North. Our winter nights sometimes get down to the teens, but not regularly. We get snow 2 to 3 times a year, from a light dusting to a foot or more, but it doesn't stay around long. So, average winter temperatures I suppose, not too warm, not too cold. The coop I built them has a few small cracks between the wall boards on the two end walls. I am thinking about leaving these un-caulked as I read the coops need ventilation and I will be sealing up their windows soon to conserve heat. So the house may be a bit drafty.

This could be a problem, not so much from the temperatures but from the draft and ventilation issues. You need a decent exchange of air to get rid of excess moisture and ammonia that builds up. The moisture comes from their breathing and the poop and the ammonia can come from the poop. The ammonia can damage their respiratory system. It will damage yours too if you breath it regularly.

Your danger from the cold is frostbite, not them freezing to death at your temperatures. If the humidity stays low and they are out of drafts so wind chill is not a factor, they really can take temperatures below freezing without much risk. But if the humidity is high, even temperatures just below freezing can cause frostbite.

You are not going to get a lot of food air exchange through those cracks or you will get a breeze blowing through. What I'd suggest is you try to stop the air coming through those cracks. but up over where they will be roosting, open up at least a couple of pretty big areas and cover it with hardware cloth for predator protection. That way the hot air that holds a lot of moisture will rise and get moved out of the coop, but they will be sleeping below the draft. My lows are normally a bit below zero Fahrenheit and I have all four of my walls open at the top to provide ventilation, averaging maybe 6" of opening all the way around. My roosts are about 4 feet up and the bottom of these openings are at 8 feet. You don't have to get that much separation, but they do need to roost below the openings.

The cold itself does not bother mine. Minbe go outside in temperatures around zero Fahrenheit as long as the wind is not hitting them. They really can handle cold better than many people think.

2. What do I do about food when I do put her out? The older chickens will be ready for a lay mixture which I have read has too much calcium among other things to be good for a chicken under 6 months old. The baby will still be eating chick starter. Any suggestions?

An easy question. Thank you. Feed them all the same thing, Starter or Grower, whatever the chicks need. Offer them oyster shell on the side. The ones that need the calcium for the egg shells will get what they need. The others may eat a bite or two, but they won't eat enough to harm themselves.

3. She is lonely. I really only want 5 chickens total, but now I'm thinking maybe she needs a buddy. She was part of the last shipment of chicks the feed store was going to sell this year. If they are no longer selling them (I plan to call today to see if maybe they have just one left), does anyone know of a reputable place to purchase one chick at this time of year?

I suggest you do a search in the Where am I? Where are you? forum for your state thread and start talking to people there. You might find someone clsoe by that can help.