best time to harvest?

At least 6 weeks to go before harvest. Harvest when the pistils/hairs are about 95% brown.

natural light takes a very long time to mature plants also if you have windows the light is coming through you are filtering out most of the uv rays the plan needs to grow thats why your not getting optimal growth among other reasons she is healthy and had about a month yet to go.

Once the pistils turn brown and recede back into the calyxes...Those still look pretty white.

Take inside each night if temperature is projected to go to low 40's. Like they said you got 6-7 weeks..I found that the biggest challenge when growing the first few times is how to hold off from cutting too early. It's like being a kid and not wanting to wait to open your Christmas gifts or shopping at a grocery store when your hungry 🤣 Is humidity bad? I grew outside this Summer and I lost almost 2 oz of northern lights to bud rot. Are you looking for a relaxed high? If so cut when the trichromes are 80% amber, thats how I do it on Indica because I go for pain relief. They say 6-7 weeks, but if you want that relaxing high you probably need 7-9 weeks.

@carjos mate those buds have only just begun to develop and won't even be close to being ready for at least another 7 weeks or probably more The glandular trichomes which are what get you high need time to develop I suggest to do some reading up on general cannabis flowering especially Maturation times etc. https://www.edrosenthal.com/the-guru-of-ganja-blog/your-essential-guide-to-when-cannabis-buds-are-ready-to-harvest Read that and get yourself a loupe for trichome monitoring and most of all try to be patient as those buds fatten

If you cut now, you will maybe get a small high for maybe 10 minutes. This plant has weeks to go. I would say about 6.

Cant really see the buds that well, but looks to me like they arent anywhere near being done, still weeks to go from what I can see.