When do chickens start laying? When they do. I’ve had pullets start at 16 weeks. I’ve had pullets start at nine months. There is no magic number for this.
Part of that is determined by when her mother and grandmothers started. Heredity plays a part. Breed plays a part too, but breed is not always that important.
Part depends on the time of year. It’s normal for hens to lay when the days get longer and stop when the days get shorter, so pullets coming of age in the spring or summer are more likely to start younger than pullets hatched later in the year. That doesn’t always work though. A few years back I had some nine month old pullets start laying the first week of December, the shortest days of the year.
Diet can play a part. Pullets fed a higher protein diet tend to start laying a little earlier than pullets that eat a lower protein diet. She’ll lay a larger egg too. My caution here is that a pullet that starts laying really young is not as mature and grown up as one that starts laying a week or two later. If you combine her immaturity with her laying a larger egg, she is a little more likely to have medical problems. I’d suggest limiting protein to a max of 20%. Personally I use less.
Say if you got 10 dual-purpose pullets from a hatchery and they hatch late winter or in the spring, I’d expect the first to start to lay maybe 18 to 20 weeks. By 22 to 23 weeks I’d expect maybe half of them to have started. By the time they are 27 weeks old I’d expect practically all of them to be laying. With your breeds, if you got your chicks from a hatchery, I’d expect them to follow this trend, but you have to have enough chickens for the averages to mean much. Four is not really a lot. Yours could be all over the place.
If you get exotic decorative chickens, they could easily be a lot later. I got the ones that took nine months to start from a breeder, not a hatchery.
A pullet’s eggs are small to start with. That’s to help protect her immature body. As she ages they will gradually get larger. After she goes through an adult molt and starts laying again, you’ll see a nice jump in size.
It’s not that unusual for a pullet to lay a weird egg when she starts. That could be a soft-shelled or even no-shelled egg, a tiny egg, one that is all yolk, one that is all whites, a double-yolker, or just weird in many other ways. The first few eggs can sort of catch them by surprise too. They may drop it from the roosts or just somewhere in the coop or run. There are a lot of complicated parts in her internal egg laying factory and sometimes it takes a few eggs to debug the program and get all the glitches out. This might take two weeks for some. As complicated as the process is, the amazing thing is that a whole lot of them get it right from the very start.