Across the country, people's baby chicks are growing into pullets.  Aww!  They were so cute as chicks, and then they went through that ugly "baby dinosaur" phase, and now they are starting to look like real chickens.  Most people start getting their first egg between now and August (depending on when chicks came out in your area).  

So what do you feed them, and when?

"Starter feed" is what you feed baby chicks, and non-laying pullets.  Starter feed is high in protein and calories, to help give those babies all the building blocks they need to grow fast and strong.  However, it does not have very much calcium.  Certainly not as much calcium as a laying hen needs.

When a hen's body is making eggs, obviously it makes the egg shells out of calcium.  It takes this calcium from the hen's body.  Hopefully the hen's diet has enough added calcium that this is not a problem.  But if your hens aren't getting enough calcium, they will build eggs out of their bones (thus weakening their bone structure).  

Feeding a laying hen starter feed also causes very fragile, thin egg shells.  It is not uncommon for the egg to break inside the chicken.  This is, as you might imagine, very bad news for the chicken!  

Most sources recommend switching to layer ration (for laying hens) between 16-20 weeks.  Whenever is convenient for you within that range - for example, when your bag of starter feed runs out!  It's better to err a little on the early side than a little on the late side.  If you had to choose between converting at 16 or at 20 weeks, I would recommend 16 weeks.  This gives the hen more time to process the calcium in the feed before she starts laying.

Another option you will find at the feed store is called "scratch."  This is a blend of grains and cracked corn, and it's very cheap!  Almost cheap enough to become some kind of cliché.  Chickens LOVE scratch, no doubt about it!  However, scratch does not have very much in the way of nutrition.

A lot of people who free range their chickens feed only scratch, along with supplemental oyster shell.  They toss out a few handfuls of scratch every morning, and keep a dish of oyster shell around for the chickens to imbibe as they wish.  

This is an affordable and easy way to feed your flock, but it is probably not the best for them.  Layer feed has a lot of nutritional extras like vitamins and minerals, and is carefully balanced to provide your chicken the best meal possible.  If you are free ranging your chickens, they have access to a lot of different things to eat, but who's to say if they are getting all the right nutrition?

Another issue with scratch is that it is very fattening.  Think of it as Twinkies for chicken!  This makes it a good snack in winter when the weather is cold, when your chickens are moulting, or if you find you need to put a bit of weight on them.

Scratch is a great treat, but just like Twinkies, it's not a balanced meal!