timing???

[Davross]

Hi guys,, when growing autos , when do you know its time to change from grow nutrients to bool mix?
mine are 4 weeks old . there is a few white hairs but not really going to bud yet, so NOW or wait?

 

[Rwise]

I may jump the gun but as soon as I see preflowers I switch.

 

[9fingerleafs]

once you see the plant is not growing taller and starts making balls of pistils, both photos and autos