Lights off before harvest?

[jashbery]

I'm going to harvest in a couple of days, and am wondering what people think about giving the plants 24-48 hours pure darkness before cutting them down. Debates range from 'don't waste your time, you're living in a dream world' to 'my god, what increased resin production!' Any thoughts from you long-time growers?
best
jash

[Revanche21]

*BUMP*

i was wondering the same thing

[medigrower]

me too.

[LOC NAR on probation]

I did not see much of any results. I know tric's grow in the dark but that much is not enough for me to tell. Some one should try a week and compair. That's what finding out what works best for you is all about.

[Divestoned]

YOU EVER SEE MOTHER NATURE TURN THE LIGHTS OUT FOR 3 DAYS AT HARVEST TIME?

Dive:stoned:

[GreenDestiny]

YOU EVER SEE MOTHER NATURE TURN THE LIGHTS OUT FOR 3 DAYS AT HARVEST TIME?

God helped out Moses with 3 days of darkness... it was for other reasons... but I bet those Egyptians had some dense buds after it was all over!

{10:21} But the Lord said to Moses: Extend your hand toward heaven. And may there be darkness upon the land of Egypt, so dense that it may be felt.
heheh.... feel those dense buds, that is!

ok, enough with my failed humour.....

If you think about it..... you're flushing the plants at the very end before harvest.... then cutting them down.... and then hanging to dry in the dark... then it really doesn't make sense to just be giving it mostly only water in the dark before ya cut them to be dried in the dark as well.

Even after the final chop they're still using their last bits of stored energy while they hang to dry in the dark. So if there is any difference it would still work to some extent that way too... I've read a couple times about growers noticing a little swelling after the first day of drying in the dark...

I'd have to see some real proof if a few extra days of growing in the dark is worth it.

[the image reaper]

after reading several claims around the Web, that a few days of final darkness before harvest are beneficial, I tried it, my last 3 harvests ... I honestly could not detect any difference, whatsoever :jointsmile: ... BUT, it doesn't cost anything to try,, so give it a shot, see what you think :jointsmile:

[Dutch Pimp]

mary jane will never tell a man all her secrets....:weedpoke::greenthumb:

[Revanche21]

YOU EVER SEE MOTHER NATURE TURN THE LIGHTS OUT FOR 3 DAYS AT HARVEST TIME?

Dive:stoned:

ive never seen mother nature give 24 hours of continuous light to its plants either... wait a second....:D

[Divestoned]

ive never seen mother nature give 24 hours of continuous light to its plants either... wait a second....:D
thats why you SHOULD NOT DO IT !! 24 hours daylight is as wrong as 3 days dark....

Dive:stoned:

[Divestoned]

the reason you need the night cycle...is thats when the plant concentrates on root growth FYI

Dive:stoned:

[moneyshotpb]

ive never seen mother nature give 24 hours of continuous light to its plants either... wait a second....:D

You have not been in Alaska in June???

[Rusty Trichome]

Might help to understand the trichome's likely purpose. The article below is the best source I've found on the broader purpose of trichomes in trees, but translates well enough to cannabis:
(I highlighted my favorite parts)

"The underlying purpose for trichomes on tree tissues is as diverse as the trichomes and the trees species involved. Roles for trichomes revolve around light absorption and reflection, tissue protection, water conservation, and microbial interactions.
Young leaves of many species use trichomes to shade photosynthetic cells until they are fully operational. As leaves expand, the effective density of these trichomes declines. Trichomes selectively block ultra-violet wavelengths like a translucent or transparent coating. Trichomes also shade tissues from other wavelengths and reflect heat energy away from leaf and bud surfaces. Trichomes help elevate the primary energy exchange interface of the leaf.
Trichomes tangle, disrupt, confuse, and prevent some types of insect injury and use. Densely wooly trichomes prevent insects from contacting the leaf service. Trichomes with defensive materials at their ends touch and stab at insect visitors. The tangle and mass of trichomes interferes with chewing caused injuries. Trichomes also provide an elevated platform upon which dust and fungal spores can be swept away by wind and water before they would touch the leaf surface.

Trichomes can help minimize water loss. Tufts of trichomes are positioned around stomates, the water control valves in a leaf, and slow water evaporation. Trichomes also form a thicker boundary layer of higher relative humidity around a leaf which slows water loss. Shading and reflectance by trichomes also lowers tissue temperatures which lessen food use and decreases water evaporation from tree surfaces.
...

Problems:
Trichomes slow wind movement and shields surfaces from rain erosion. Some trichomes help protect tissues by softening abrasion and bruising contacts. Unfortunately, the trichomes that protect in one way facilitate damage in other ways. Trichomes form centers of surface wetting that can accelerate leaching and cuticle damage. Acid rain damage can be isolated around trichomes. In addition, some pathogens depend upon spore germination above leaf surfaces.
Trichomes come in many shapes. Some trichomes are long and thin, matting down in a thick felt-like surface. Other trichomes have multiple branches that looks like a tree in miniature. Still other trichomes have a circular crown of branches which are star-shaped. Some trichomes are colored with a pigment or develop a color from weathering and from the environment, but most trichomes have no color. Trichomes do not have chlorophyll.

Tree Trichomes: Big Hairy Tree? (http://warnell.forestry.uga.edu/service/library/index.php3?docID=161&docHistory%5B%5D=2)


If there was to be any type of benefit, I believe it is immeasurable and subjective to the common cannabis gardener. The only instance I can think of that may validate this notion, is if the trichome purpose in cannabis is to protect from UV. Then the plant, which is expecting sunlight soon, produces more delta-9 or CBN's/CBD's in anticipation of a morning that never comes.
But then again...this could be an argument mor geared twords 48-72 hours of solid daylight before harvest, too.
Would be a great lab experiment if you had the right equipment, tho.

[Revanche21]

yea I was also wondering if you gave it 24/0 light instead of full darkness what the effects would be.

btw I think the roots grow in the darkness thing was dispelled? or rather up in the air.

[stinkyattic]

Re: Alaska in June; cannabis plants that occur naturally in very high latitudes have an autoflower trait to deal with that (C. ruderalis, Siberian hemp).

Re: Darkness- Cut and hang your plants out of direct sunlight or intense HID light. Beyond that, it's not really important. Personally, I'd give them a normal schedule right up to the end. I'd worry about extra light because it doesn't take a plant, especially a ripe one, very long to start popping nanners and possibly knock up any plants you still have in your flower room.

[jashbery]

Thanks everyone for this very interesting thread. I decided NOT to give them that extra darkness given the general tenor of conversation here, and have chopped the two girls down. This has not been an astounding grow by any means, but given that they survived very cold water, nutrient burn, overheating, and any number of other bumps along the way I'm OK with the end results!

all best until the next grow and - most probably - a whole new set of 'issues'!
--jash

[killerm8r]

Yes, indoor growers are trying to replicate conditions found in nature.

HOWEVER, the constant mantra "have you seen mother nature do _____" is stupid for exactly the same reason that doing things completely different than mother nature is stupid. Neither extreme is automatically correct. Have you ever seen mother nature grow weed without sunlight and dirt? No. Does it work? Absolutely.

If you're growing indoors you're already trying to improve on mother nature. You don't get 18 hours of constantly bright sunlight in nature. You don't get 100% sunny days in nature. You don't get ideal temperatures, humidity, and nutrition in nature. We're optimizing, perfecting, and tweaking every single little thing to try to help our plants grow as well as they possibly can.

So the argument that if it isn't found in nature it shouldn't be replicated indoors is flawed.

The only question is: does it help the plant achieve the end we want it to?

And guess what - we don't always have the same goal in mind as the plant. Do you really believe the plant's goal is to begin and never complete its reproductive cycle? She wants to reproduce, to create seeds. We try to prevent that. Carrots, garlic, and similar plants spend all of their first year creating massive root storehouses of energy for the reproductive cycle their second year. We interrupt that to dig up and eat the yummy parts.

I've seen some research that indicates a prolonged darkness cycle at the end can trick the plant into believing a massive frost is about to come, which the plant responds to with a final surge of reproductive effort - to try to get the seeds made and safe before the winter comes. Does that actually work? I don't know.

But I'm not going to discount it simply because we don't see several days of complete darkness in nature.


If I wanted to grow entirely by nature's rulebook I'd grow outside.