Last week before flush maybe.
Update: smallest stopped drinking 2 days ago, thank god i started flushing it early on. It’s stumped that i presume 20g dry :/
Update2: microscope assured amber resin all over the small stumped one, she had to go.
@Butrub, you very welcome buddy. Personally I would not start any bloom nutrients untill they are in flower. If using too early may affect your plant development and reduce your final yield. Peace and love✌️💚