Purchased NL feminized seed from ILGM back in January sprouted in late February with a 100% germination on 12 seeds. I veged for roughly 8 wks with 16/8 light cycle then April 14th switched to flower with 12/12 light cycle. Its been 73 days in flowering and no color change in tricomes but all are heavy milky with no amber other than very little on sugar leaves. My grow is in coco in a completely controlled environment, i was under the impression NL was a quick flowering/harvest strain with 7 to 9 week window.but that doesn’t seem the case here. Just wondering if I’m missing something about NL would like about 10% amber before harvest however not sure how much longer it might take now goings on 11wks since the 12/12 light switch any thoughts would be appreciated.
NL is usually a 8-9 week flowering strain, but sometimes they can go 10-11. If your trichs are all milky, they are at peak strength and in the harvest window. Some amber should show up but occasionally they don’t change. You will be fine chopping if the trichs are all milky though. And welcome to the community too!
My experience it’s always been 10 wks minimum on NL
Your math doesn’t account for the transitional time. Have to subtract that time so you’re at the very least day 59 flowering/8.5 wks
First time with NL but happy with the grow, just expecting or assuming they’d be finished by now. My electric bill here in Texas with this heat is a burden on my pocket book i usually don’t grow in June,July or August but these ladies are pushing the envelope and my patients.
I guess it’s a transition period but exactly what’s the norm for that ?, I’ve had hybrids flower faster than these NL ladies. Thanks for your response.
Transition takes 14-21 days to call it wk1 flowering
Then why not just add that to the 12/12 flip time and say 12 to 13 weeks for that strain, 3 weeks of transition seems a bit long. Thanks again for your response Happy Trails.
Well how would that work for outdoor growers: where the transition can be up to 1.5 mos. The variables of long day or short day, based off location to the equatorial line. Breeders can’t make blanket statements like that. They know what week 1 flowering looks like. They give you a baseline form of start, and base an estimate average off their outcomes from their testing.
Not once you know what true flowering wk1 looks like. I’ve had them go 23-24 days before I’d call it. It’s almost always more than 14 days but people just say, “I’ll ‘just’ call it day 1 of flowering.” That doesn’t make them correct. 
Those same people are the ones that complain that the breeders estimates are always off.
Outdoor grow is a different animal all together, there’s no switch of lights or transition period to speak of as far as 12/12 switch its up to mother nature not the grower as far as time lines. I was referring to controlled environments and in that case the grower has control of everything from temperature, humidity, medium, container, lighting everything about the grow except genetics. I understand what your saying but in a completely controlled situation surely a better time line could be had instead of adding two to three weeks on top of 7 to 9 week flowering time. Just a little confused about a breeders time lines on flowering plants when the grower controls everything about the grow except genetics in a particular strain. Indoor and outdoor grows are completely a different type of grow leaving everything up to mother nature is why I grow inside a grow room inside a building so I have complete control. Thank you for your foresight and truly love 
growing Marijuana. HAPPY TRAILS.
Welcome @Willie127 !!
I’m not an Uber-grower, and over the years have simplified my harvest windows. It works indoors or outdoors, photos or autos, for every strain I’ve ever grow:
When the trichs are where I like them, I chop. (Personally I prefer more of a head than a body effect, so usually shoot for clear/going cloudy). Test buds when close taste green, but give a great indication of where things are at.
I pretty much ignore predictions on harvest times, because even within a certain seed run beans can be slightly different.
I hear you about the heat. Here outside of Houston it’s been hotter and damper than two squirrels doing naughty things inside a wool sock.
Harvest Wishes!! 
Don’t harvest them early. I’m a frequent flyer on the northern lights express. I also live in a hot location and I understand about the electric bill, but I have found particularly with Northern lights and OG Kush that they take at least 10 to 11 weeks from when you flipped your lights but from when you started seeing flowers . If you don’t wait it out, your buds are going to be very light. Most of your weight gain happens in your last week. You’ll be able to tell because your plans will stop drinking and you’ll get anywhere from 10 to 30% amber. Just my personal experience. It’s a horrible thing to grow something for that long and then regret chopping it a week too soon
Mr Viejo I’m a little older than you ( old school ) and live in East Texas about 70 miles SE of Dallas. Thought I’d planned to avoid June, July and August heat but seems my ladies disagree. I’m 10 weeks and 4 day’s s since the 12/12 light switch and thought surely there’d be some amber by now to avoid the dog day’s of summer. My ladies are NL and showing nearly 90% milky with only less than 5% amber just on sugar leaves. My goal was to have them drying by now since the flowering time was 7 to 9 weeks supposedly then some comments here say 14 to 21 day transition period required before the actual flowering count down. That being said then the actual flowering period isn’t 7 to 9 weeks it’s more 10 to 12 weeks. With a heat wave coming in this next week I’ve decided to chop this weekend with near no amber trics but close to 100% cloudy. In your experience with NL will waiting on amber be worth the constant monitoring and expenses to carry them any further in the flowering when thinking a few day’s could lead to weeks in this excessive heat and humidity. I’m a small time home grower for personal use and close friends with having to use my grow room as my dry room the only way to control the elements which will be easier with lights out temperature wise. Just thoughts on quality not quantity amber vs milky in the final product when in my area heat and humidity plays a huge roll on harvest window and total expense of a grow.
@Willie127 , when to chop is a very personal choice. I can’t give you a straight answer, but I will say this:
My personal preference has always been to harvest early, mainly because I like a more active high. Typically for me that means trichs look kinda like a basketball on a finger (meaning full and round).
Some folks prefer all cloudy with some amber, some go full amber.
I like to nip a small bud and do a quick dry in the oven (lowest heat I can get, turning often with the door cracked). The flavor won’t be there, but I can at least gauge the effect.
I used to grow in my garage in the high desert, no ac, and summer was always tough.
Can y’all post a picture of what your gal is looking like right now?
@Willie127 welcome to the grow family my friend happy growing
I have harvested northern lights and other strains early due to pressures from pests or other things like temperature and humidity. If the Flowers are dense and the smell is there and you have all cloudy mitigate the risk and go ahead and chop