First run

Hey! You've still got a bunch of white pistils so yeah roughly 4 weeks left.. Harvest window opens when you start getting amber pistils. The best way to check is looking at the trichomes on the buds with a 60X magnifying loupe Clear trichomes haven't reached their full potency, cloudy ones are full of THC and amber are losing THC while gaining CBN. I harvest when after examining and finding 70% cloudy trichomes and 30% amber trichomes. For me that's a prefect combination, depending on the strain as well. With some strains I go with lower amount of amber trichomes but always attest 10%. This really depends on what type of high your looking for. As for what they look like, clear trichomes look like shiny glass, cloudy like plastic and amber like resin The red stems can be magnesium or phosphorous deficiency but I don't see any other symptoms that suggest it's that.. some leaves seem to be turning yellow but that could easy be the light reflection in the picture.. Red stems can also be from the cold or as you've said from the light.. like a tan if you want to call it that way.. Hope this helped. Good luck and happy harvest!