foliarfeeding

Wasn't sure where to post this, but I guess it's a advanced topic... I've just purchased a small water atomiser to sit in my propagator with my clones and have a query on foliar feeding. Do you think it would be possible to add a 1 part nutrient at say 25% concentration and use the atomiser to...

I've been foliar feeding throughout veg with kelp and humic acid and my girls love it. Now I know not to spray fully formed buds. But how long can you foliar feed into flower? Not past week one? Week two? I feel like once I'm in week three definitely don't but just wondering if anyone else had...