Auto lighting

[Shotgun185]

So I know this subject has been talked about a few times.

what is people’s thoughts on lighting schedules for autos at the end of flower.

im now on my last week ish of flower and want to know if there is any benefit to me, turning the light down from 20/4 to say 18/6 or 12/12

or will this slow the whole process down on the plant? I.e: thc production? 
Or does it do the opposite and give the plant more time to produce more thc at a faster rate? 
im gona tag @brock1 in on this as I’m sure it was him who said it is better (not 100% it was him) 

Any reasons for and against? 
cheers 

 

shotgun 

[sweettooth]

Never done autos but as you can grow them under 24/7, I think moving to a 12/12 would limit the last week of bud production. Having a search online, there are many good threads on various seed banks / breeders / growing mags

 

24/7 = maximises harvest & more electricity required

20/4 or 18/6  = good harvest & Energy Saving

12/12 = smaller buds & increased energy saving

 

The only thing I would do and this also is applicable to photo period strains is reducing temps and maybe ppfd in the last week to keep those terps healthy

 

[Shotgun185]

Nice one @sweettooth

yer I’ve had a good look about, to be fair and that does seem to be the case, but I’m sure it was @brock1 who said he would never finish an auto on a high light schedule?

Im not to worried as these are my only autos and then I’m on to photos. Just wanted to get the best out of the last week for them! 

[brock1]

59 minutes ago, Shotgun185 said:

Nice one @sweettooth

yer I’ve had a good look about, to be fair and that does seem to be the case, but I’m sure it was @brock1 who said he would never finish an auto on a high light schedule?

Im not to worried as these are my only autos and then I’m on to photos. Just wanted to get the best out of the last week for them! 

Light degrades THC in the trichcombes. Yes it also causes photosynthesis which produces proteins. Which is a big part of what makes a plant bulk in principle because it took energy from the light and made it into matter. I grow for quality over quantity & every little bit adds up to a lot. For me auto's that are grown under 24hr are plain boaring low strength in comparison to same strains grown under fewer hours. 

Edited August 1, 2023 by brock1

[Shotgun185]

Cheers @brock1

is there any point of dropping the light hours down from 20/4 in the last week - week and half? What do you finish your autos on? 12/12? 

[brock1]

58 minutes ago, Shotgun185 said:

Cheers @brock1

is there any point of dropping the light hours down from 20/4 in the last week - week and half? What do you finish your autos on? 12/12? 

I finish them with 48hr of zero light. It depends were I am growing the auto. If it with mothers its 18-20hr if it in a flowering grow I go between 8-13hr depends on what strains i have growing at the time.

[brock1]

I should also point out that light dosent always mean bigger buds. A lot of sativas will produce tighter harder buds if your give them less hours of light. I have been as low as 8hr light in the past with sativas. Point as theirs no rule because all lines are different. If you like a strain you need to work out what works best for it if you ever want the best it can give 

[Shotgun185]

Nice one mate

As usual a top explanation from @brock1

[disco survivor]

Asked my mate this question (he's a commercial grower of tomatoes and cucumbers under glass). He's a botanist and talks fast so a lot of what he tells me goes straight over my head. The bits I got from our conversation this evening - blackout periods are just as important to plants as light is. Without blackout periods, plants cannot produce a key component - Phytochrome. Also, Stored energy produced during daylight through photosynthesis, is used by the plant during darkness to grow (think that part is right?). Without sufficient blackout periods, a plant will experience stunted growth, lower yields and are more susceptible to disease.