When do young chickens sleep on the roost instead of the ground?

[horsepowerhaven]

My 6 month old chicks are great free ranging and going into the coop at night, yet the 3 of them huddle together on the ground while the adult hens perch up on the roost.

I'm not sure if it is because my roost is small for the number of chickens I have (building a new coop soon), or if they just prefer to huddle together on the ground for each others comfort. It isn't to keep warm, as I'm in AZ and the temps at night are still hot, with 100+ degrees during the day.

This is my first time raising babies--any thoughts/advice?

Thanks!

 

[Clay Valley Farmer]

Might be a pecking order thing? I have a little 7-8 week old barred cochin fluff ball that flaps and crawls his way up onto a 3 foot roost, off the step of the pop door, up onto the feeder then across to the roost. Some times a little trainer roost 6 or 8 inches high gets the birds into the idea of it, seems to work for my young silkies.