In an interview with Dr. Bruce Bugbee around’ish a year or so ago, he stated that 48 hours of light before harvest is actually more beneficial for the plant than darkness. I couldn’t find any other articles or video’s related to doing a 48 hour light period, only info on the now debunked darkness cycle before harvest. So I wondered if any you have tried it or had educated thoughts on whether or not it had or would have any noticeable benefit to the harvested bud? I am at the end of my first grow and heavily debating doing it even though I have no previous experience or harvest to make any sort of comparison to.
8 Likes
Not sure if two days of anything at the end of the grow would show any noticeable differences. Light or dark. Some people drive a nail through the stem to stress the plant out and only harvest in the dark. Weed growers do some weird things. I used to put things in the dark and stopped because I never ever noticed a difference but that’s what my uncle told me to do so I did it for years lol
15 Likes
Yes, this is the conclusion I’ve also come to when I’ve been reading more scientific methods of doing experiments with these type of methods.
What seem to give the highest quality is giving a stable environment that cover all needs. Unsurprisingly 
Pz 
18 Likes
According to Dr Bugbee, studies done by colleagues of his but not by him, the extended light helps the plant produce more terpenes in that final period before harvest. I’m not attempting to debate, just offering what was said in the hopes of starting a “fruitful”(pun intended) conversation.
9 Likes
I just keep it simple. I don’t even flush anymore….gasp
18 Likes
Just let them do their thing. Easy enough.
18 Likes
I give them 48 hours of darkness. Years ago someone convinced me it helped get a plant to finish up and squeeze out more resin. All my plants end up maybe a little stiffer. I always figured extending the light would cause them to start to revert or hermie.
1 Like
Let the plants do their thing. Get a couple harvest under your belt, so you can get a baseline of what to expect and then start experimenting.
I did 18/6 for 8-9 days before harvest once because more light = more energy and I had some humidity problems at night, so it eliminated that issue. Did the extra light make a difference in the final product? probably not.
2 Likes
This is the way
2 Likes
I had to leave for awhile so I broke the light cycle and put the plants in window light with a longer photoperiod. No difference.
The only reason I would do this is if I want to reveg my plant after I harvest. Switch light cycle a week before harvesting. Never noticed any extra terpene or trichrome production.
2 Likes
Nice, I could see where that would help on a re-veg a lot. Have you ever noticed a plant throwing a nanner because of it?
2 Likes
was that the mr grow it interview? i only remember him saying that 24-48h of darkness was useless (which most of us here agree/know)
ive done the light for 24 hours accidentally hahah, the plants didnt stress at all (remember it takes a few days for them to revert) but i didnt notice any improvements either. i know many have told you to just let them be (sound and good advise) but also, this isnt heart surgery so why not go for it and let us know?
5 Likes
Someone said, the friend of a friend …
Most of looping questions are more than answered in general.
48 hours of switch don’t have enough weight in the plant anyway, cannabis and even hemp take a week to fully adapt to a new photoperiod.
Look at it (i know no one will read the study lol)
And please, pay at least attention on how is reacting the plant during the night. She prepare herself in using phototropism to be ready for the lights, BEFORE they are ON. They have their own timer, and you don’t change it just like a computer. It take time to adapt their cycles of production (co2, hormons, sap enrichement, etc …).
8 Likes
Definitely have seen nanners show up late with the light switched but I can’t say if it was the light change or just late stage attempt at rodelization as it happens with some cultivars without the light change. Most plants I’ve done it with were fine so very much could be based on the genetics used.
1 Like
I do, but I’m in Hydro and it seems like a waste of nutrients. Once I decide its done I’ll go pHed water for a few days just to be sure its done-done
1 Like
You’re taking his statement out of context.
He was on Mr Growit & was asked about 48hrs dark period before harvest & whether it had any benefit. . … the bro-science thought process is that terpenes are developed in the dark so chopping after a lengthy dark period can result in higher terp levels.
His response was that, terpenes are actually developed during light hours and NOT dark hours, therefore a 48-hr LIGHT period would be more appropriate, but, i recall he did also indicate you can’t create any magic in those last two days.
Pretty sure it’ll result in some nanners on your top buds, if you wana risk it go ahead.
4 Likes
Nice, yea, I’m in promix HP and I just leach plants with plain RO the last two or three weeks and use up the built up salts in the medium while they finish. I never achieve a zero ppm run off during the leach as I don’t water until runoff anymore. the plants are still definitely feeding without having to waste nutes at that point. the lowest I’ve got the run off to be was 500-600 ppm by harvest date and that is the only time I usually water until runoff, gives me an idea of what was left I. The soil. I used to try and achieve zero runoff a couple weeks out but my plants always yellowed out too fast. I don’t even PH the RO during the leach phase in promix. I’m all about finding that lazy sweet spot lol…
2 Likes
I’ve experimented with stem splitting, UVA, and UVB. I believe I saw a good increase of trichome production with the UVA and UVB addition but not a lot from stem splitting or putting ice around the stalk the last 2 weeks
2 Likes
Okay, what about this…
I had some pepper plants started in the grow closet, they were about a foot tall with no sign of flowers. I left them in the closet with NO LIGHT for 5 days. When I came to plant them, they had flowers all over.
So would 2-5 days of pure dark (or maybe 2 hours light) kickstart flowering in cannabis?
Ultimately the question is…would 2-5 days of light deprivation at flip to flower shorten the length of time it would take to show sex and start producing buds? Rather than waiting 2-3 weeks for flowers or balls.
I may use my current crop as a test.
2 Likes