how to encourage all hens to lay

[joycorbin]

I have 5 hens: 1 bantam, 2 redstars, and 1 redrock who're all around 5 months old-old enough to be laying. My wonder though is why all my girls are not laying; on average I'm getting 2 eggs a day. I know my bantam has only laid 1 egg because it was blueish, but I'm not sure who's been laying the laid eggs. I've received maybe about a dozen so far.
How can I encourage ALL my girls to lay?

 

[TwoChicksChix]

Some chickens just take more time than others. Some won’t lay till 6 months and I’ve had some that didn’t lay till 9 months. It’s just a waiting game.