Start fertilizing

I prefer to start giving Nutes when my Plant shows it to me 👍 So is start when the bottom Leaves start yellowing. Hope this helps. Good Luck with your Grow

And yes...ProMix really is amazing at holding nutrients that's why I say use less when you start feeding. And don't ph your water! Pro mix does that for you.

Generally I start to feed my photoperiod plants around week 4-5 in soil grows. Unless of course demands it at week 3 then give it early but I always start with a little less then the suggested dosage to let the plants get acclimated to the feed. Hope this helps

Since you're using Promix I would say you are good until probably a few weeks after your transplant into a larger container if you continue using promix. I would say probably not for another 3 weeks.