Laying age for partridge plymouth rock chickens?

[something witty]

My five girls are 21 weeks. They have bright red combs, and are obviously mature. Three of them have begun to squat in front of me. This started approximately one week ago. They have shown some interest in the nesting boxes, as evident by the depressions in the nests. I have yet to see one in the nest, however. Anyone with experience with this breed remember when theirs laid?

 

[Kelsie2290]

I kept five of them this spring, hatchery birds, and think the first egg was right at 20 weeks and the first day I got 5 eggs was when they were about 25 weeks (they may all have been laying before that, but didn't all happen to lay the same day.) So if they are squatting, I'd say you can expect your first egg within a week or two.

 

[Fred's Hens]

https://www.backyardchickens.com/t/273471/plymouth-rock-thread/4680#post_11987014

A few responses to your question posted above.