Did you know that eggs are seasonal? If you've never had chickens, or regularly purchased eggs from your local chicken owner, you may not have been aware of this, given that the availability of eggs at the supermarket rarely seems to change (pandemics notwithstanding). But your local egg producer knows very well that egg production, like the beautiful foliage, drops off in fall.
Many people think the decrease in egg production is due to the onset of colder weather. Although extremes of temperature (both hot and cold) can affect egg production, it's actually the shortening days that are to blame. Hens need around 16 hours of light a day for optimal egg production, but for most chicken owners the drop isn't really all that noticeable until after the autumnal equinox. That day, usually around late September, is when there are equal amounts of day and night. For many chickens, dipping below that 12 hour mark essentially stops egg production. Why is that?
Supplement the light! It turns out that even a 40w incandescent light bulb can stimulate hormone release. For best results, use a timer so that the light comes on early in the morning, after 8 hours of darkness. True story: when I first tried this, I used the timer to just add daylight and make the day longer. My chickens, bless their hearts, were so confused. In case you didn't know, chickens "put themselves to bed" every day, going into the coop to roost as dusk closes in. But once my chickens got inside the coop, the "daylight" they saw told them to go back outside and scratch for bugs. In. Out. In. Out. Eventually, some of them got shut out for the night by the automatic coop door. We ended up out there, with our flashlights, trying to find and collect chickens so we could put them up for the night. Needless to say, the timer got adjusted to come on at 3 am!
Another word of caution here: make sure the light is situated as far away from the (many) sources of combustion available in most coops. I use a "droplight", so the bulb is enclosed in a cage, and it's hung in an upper corner of the coop, away from where the chickens might accidentally bump into it. Even if they did, all the extra cord is secured outside of the coop so it couldn't fall to the pine shavings on the coop floor.
On a philosophical level, some chicken owners don't feel right manipulating light to fool Mother Nature, and have accepted the fact that eggs, like tomatoes and apples, are seasonal. However, I haven't been able to find any evidence that light manipulation shortens a hen's life or causes other health issues. For our farm, then, so as long as the hens are provided with adequate supplemental nutrition during the fall/winter and are given time to molt, we're comfortable with producing year-round eggs.