How quickly do I turn up my lights during flower?? I'm at 75% on week 4 flower… i don’t want to over do it…

You should be at 100% two weeks ago. What is your wattage? I use 300 + 100 as support lights and during the first two weeks already in the veg phase I naturally dimm my set up to 100% in just four to five days...what you are doing with 75% on week 4 is loosing precious power on your veg phase that is probably the most important time to have full power on your set. Good luck.

Flowering = 100%........no need to be afraid! You will not be over doing it.

normally people go from 18/6 to 12/12 and increase its intensity or lower its hang height on the lights to match a PPFD map of their growing area. Others calculate their DLI useing light meters and mimic the same thing. I'm a fan of the DLI calculation. I borrowed a light meter from my grow shop and make a PPFD map of my tent with my lights on various intensities and found out at 30" hang height with my lights I need to do 16/8 at 40% in veg and 11/13 at 60% in flower for a DLI of aorund 37-38. Cannabis maxes out aorund 40 DLI without any added CO2. When you add in extra CO2 you can go above and beyond a DLI of 40. But everything else must be in check and your grow room has to be sealed or its wasted CO2. I don't like added CO2 I think its wasteful. A cheep way to achieve some similar results is judging how your plant is growing based on its current lighting and adjusting. Little to no spacing between the nodes is a good sign its light is to strong and wants less of it. Move the light further away or dim it down. Long and large spacing between nodes is a good sign it can use more intense lighting. Move the light closer or increase intensity via dim knob and tun it up. Good Luck!

Hello! I've recently been fine tuning my light strategy. So the research is fresh in my mind. However, we need to know more about your situation. 1. How many watts? LED? HPS? 2. Grow room area and light size 3. Autoflower or photoperiod? This will change your DLI strategy