How early do I start nutrients?

The plant has about two weeks of nutrition built into I when it pops. So, most people like to give them nutrients at that point in time. I give my plants nutes once it pops because of what I use. I grow straight organic and the nute line I use takes a couple weeks to break down and become soluble for the plants. So, even though I give the plants nutes when they pop, they aren't able to eat them until they run out of built in nutrients. I hope this helps.

is it auto or phootoperiod? is photo can give once the cotylons start to turn yellow

well it depends what you’re growing in if you’re grown in soil you don’t normally need to feed for the first couple of weeks as there’s nutrients in the soil, (but check what soil you have) Coco i Believe you will need to feed buy slowly ween them onto it, wherever you get your nutes from that should give you some sort of guideline/timetable of ratio to litre and for what your growing in, Good luck 🌱

When growing in soil after 2 weeks. When growing hydroponic from the start. Happy Growing! 😋

I start usually 2 weeks after germinating