What ages should I start looking for eggs from my hens?

[Chicken Fruit]

I have

EE's, a welsummer, BA's, a light brahma (maybe two)... When will the ladies start to lay? Its 20 weeks too soon to hope for eggs from someone?

Edit: the oldests are 11weeks, the babies are still just 7.

 

[columbiacritter]

18wks is the average, some lay a bit before, some several weeks later.

 

[Chicken Fruit]

anyone have any person experience with those breeds?