how old do the baby silkies have to be before they go outside. have large pens, nesting boxes in the pen. hay and shaving in the pen. the chicks r 10wks and the others r 8 wks old. they r in the laundry rm. but am ready for them to go out. They r in a large cage. Temps here r about 18 to 40 degrees at night.. I can lock them in the nesting boxes at night.