When do your pullets start to get bigger combs and waddles?

[undergroundchickens]

I have six 15 week old pullets. I was wondering when they will start to develop some noticeable comb and waddle growth. I have 2 barred rocks, 2 RIR's and 2 EE's. I see pictures of these types of chickens at about the same age and my girls combs and waddles are sure lacking in both color and size. Is this something that comes on quickly before laying begins or are my girls just way behind for some reason??

 

[gritsar]

My brahmas pullets started "reddening" up close to their point of lay. For most of them that was around 5 months, but for a couple of them it was much later.