One of the main reasons people get chickens are for the eggs.But there is much more to know then just the chickens laying a egg. Many chickens start laying at many different times. Why?Because some breeds are meant for good production, and usually breeds like this, will start earlier then others. For instants Sex links (black Or red),tend to start at about 4 or 5 months, but stop earlier the most breeds due to their egg cycle being worn out, while breeds like silkies may not start till 7 months, or even later, on occasion 3 1/2 old chickens may start laying, rare but very much so possible. Why hens suddenly stop or never begun? Sometimes it's due to weather. Cold, snowy, wet weather may cause hens to drop, and pullets to not start till warmer weather begins, mainly because no one likes to be cold, right. If it is too hot out and the hens are stressed with heat, they may not lay. Daylight hours also and a lot of times have something to do with decrease in laying or late laying pullets. Too many roosters, or just too little hens, or even a rooster who just is a vigorous breeder could also have something to with why your hen are not laying,over-mated,stressed hens may stop, or decrease in laying. Molting can also be cause. Molting is an uncomfortable stage where hens begin losing old feathers and grow new ones, it is a stressful and sore process and usually hens will not lay until a few weeks or days after their molt has ended. Signs Chickens will soon begin laying-You should defiantly start setting up nest boxes, or open nest boxes up to the hens at about 4 months, regardless of the breed, just be prepared. Some things to look for are, comb development. Color of comb (usually is beginning to turn a light red color.),waddle development too, their vet may begin getting wider (although that is more common once they have begun laying.),vent may be pinkish, they may e squatting for you, or if a rooster is present they will squat for him (an example of the soon to lays squat or submissive squat,)Also, visiting the nest boxes frequently, or even making fake nest. Soft eggs shell what to do? Most people give their chickens grit, and oyster shell. Oyster shell helps keeps egg shells hard, but not hard enough to the point you can barely get it cracked (although overdosing hens can have this happen).You want to give them this once you have noticed egg laying. There are also layer feeds that already have extra calcium in it (advise not to give this to them if you have roosters, roosters do not need extra calcium.) Grit has nothing to with these eggs. It is given to help them digest food better. For both of these things you should give free choice to, and have it out 24/7.Although,free range hens do not need a lot of oyster shell. How long should I expect chicken to lay eggs? Hens usually start slowing down around 3,but that does not mean their done for forever. I have 5 year old hens who seem to be laying quite often,and 4 year old hens as well.Red and black sexlinks tend to burn out quicker then other breeds. Chickens do live up tot heir teens when kept and good condition and will lay through all those years, while some may stop,do not expect to get eggs everyday form older hens. I actually have a hen who will sit in the nest boxes, even begin cackling and walking back and fourth through the chickens house,make a nest sit for a awhile, get out and not lay any egg, on occasion we may get a green egg. She is an Easter Egger. who we know for sure Is old.