light cycles and spectrum to finish faster

caretak3r

caretak3r

Well-Known Member
I'd like to start a discussion regarding light cycles and the use of specific light spectrum to encourage the plants to finish as fast as possible. I'm specifically referencing shortened day cycles (less than 24hr) as well as the use of 730nm light at lights out (and anything else people have experience with). I'd love to see @churchhaze / @Positivity / @captainmorgan / etc chime in as it seems you guys have made observations in other threads that would be relevant.

Thanks!
 
BOBBY_G

BOBBY_G

Well-Known Member
seem sthat not just spectrum, but maybe light tech makes a difference (cob or CMH vs HPS). im sure a lot of that might be spectrum, but there might be other factors (in this example maybe LACK of far red HPS spectrum is responsible-see people 'finishing' with 10K MH)

im sure co2, nutes, and light intensity are also factors
 
FranJan

FranJan

Well-Known Member
caretak3r said:
I'd like to start a discussion regarding light cycles and the use of specific light spectrum to encourage the plants to finish as fast as possible. I'm specifically referencing shortened day cycles (less than 24hr) as well as the use of 730nm light at lights out (and anything else people have experience with). I'd love to see @churchhaze / @Positivity / @captainmorgan / etc chime in as it seems you guys have made observations in other threads that would be relevant.

Thanks!
Click to expand...
Here's something 4 u.

I never bought into the Illumitex F1 spectrum (660,730,~5000K in a 2:1:1 ratio) accelerates flowering schpiel Illumitex and their paid/compensated growers and partners have stated over the years but after my last few grows, which have been with mostly Illumitex F1s doing the heavy work, I've noticed my plants have not looked the way organic based cannabis grows should look when finishing and now I'm starting to realize that it just might be my plants are finishing earlier than expected. Plants I have grown from clones before, so I know how many weeks they take. Plants I have feeding techniques down cold for are now devouring themselves overnight. Perhaps because I'm missing their new feeding schedule? An 8+ week Goji just finished in ~6 1/2 weeks but it was a re-veg. I've got a 9+ week Cali Connection OSD+ SOG in there and recently she just went south on me all of a sudden then I fed her like a maniac and now she's just chugging along. She's getting some solid nugs now and might be done by next week which will be a little early by my calculations. But it's no magic time machine. Yields are somewhat dissapointing with this new setup, there's beens some grower error in there but quality is still up which is OK with me atm. Now I've got my old faithful 10 week Black Widow in there. She's a solid yielder too so I think I might get a clearer picture of what's going on if she finishes in ~8 1/2 weeks.

But here's what your topic really made me think:
Any spectral effects that manifest themselves must first start with an efficient light source intense enough to produce photosynthesis with the degree of the effect(s) dependent on the grower's ability to match the growing environment to the MMJ's genetics. In other words someone get me a monster 4000K 70 CRI COB and pass the Bud Candy :P!
 
captainmorgan

captainmorgan

Well-Known Member
I've used 730nm as a phytochrome trigger for over 3 years now and won't flower without it at this point. I originally used it to increase yield with the longer light schedule but also noticed a shorter flower time. I use it during the entire flower cycle with a 12/12 cycle at the beginning and end of flower and 13.5/10.5 in between.
I get a noticeable bump in yield and about 7 to 10 day shorter flower time depending on the strain.
 
G

grouch

Well-Known Member
I have heard amber trichomes appear sooner when using UV-B. Maybe add some reptile bulbs in and run them all the way through flower.
 
FranJan

FranJan

Well-Known Member
captainmorgan said:
I've used 730nm as a phytochrome trigger for over 3 years now and won't flower without it at this point. I originally used it to increase yield with the longer light schedule but also noticed a shorter flower time. I use it during the entire flower cycle with a 12/12 cycle at the beginning and end of flower and 13.5/10.5 in between.
I get a noticeable bump in yield and about 7 to 10 day shorter flower time depending on the strain.
Click to expand...
Have you ever thought about what would happen if you used 660nm for 15 minutes before having the COBs come on? If 730nm puts them to bed faster, would 660nm have them ready for lights on the moment the COBs turn on? Or is it like what previous growers have said that it just doesn't matter? Lights on is lights on. I don't agree with that since we're talking about a process a plant has to have to have it's it's Pr turned into Pfr before continuing lights-on flowering for the day, no? Or is the process converting Pfr to Pr faster than converting it back and thereby really making little to no difference with lights on?
 
captainmorgan

captainmorgan

Well-Known Member
FranJan said:
Have you ever thought about what would happen if you used 660nm for 15 minutes before having the COBs come on? If 730nm puts them to bed faster, would 660nm have them ready for lights on the moment the COBs turn on? Or is it like what previous growers have said that it just doesn't matter? Lights on is lights on. I don't agree with that since we're talking about a process a plant has to have to have it's it's Pr turned into Pfr before continuing lights-on flowering for the day, no? Or is the process converting Pfr to Pr faster than converting it back and thereby really making little to no difference with lights on?
Click to expand...
Like 730nm,the needed 660nm for state change is small and the new high end COB's have plenty of it for state change. If your lights source has no 660nm then a small trigger would be needed at lights on.
 
medicinehuman

medicinehuman

Well-Known Member
I ran 3 26w 10.0 UVB lizard lights all through the 12/12 cycle on an Afghan Kush once and it finished a week sooner and was potent but lost some grams as far as final weight. It was noticeably less than normal for that strain then when I grew without the UVB. I still run them on some plants but only for about 30 minutes a day.
 
C

churchhaze

Well-Known Member
FranJan said:
Have you ever thought about what would happen if you used 660nm for 15 minutes before having the COBs come on? If 730nm puts them to bed faster, would 660nm have them ready for lights on the moment the COBs turn on? Or is it like what previous growers have said that it just doesn't matter? Lights on is lights on. I don't agree with that since we're talking about a process a plant has to have to have it's it's Pr turned into Pfr before continuing lights-on flowering for the day, no? Or is the process converting Pfr to Pr faster than converting it back and thereby really making little to no difference with lights on?
Click to expand...
If you used a 660nm pulse before lights on, you would bring %Pfr to ~85%, but once the lights came on, %Pfr would quickly converge at a much lower value due to all the amber, green, and the small amount of far-red in the spectrum.

The reason a 730nm pulse after lights out is helpful is because it works to lower %Pfr faster than darkness does.
 
BOBBY_G

BOBBY_G

Well-Known Member
captainmorgan said:
I've used 730nm as a phytochrome trigger for over 3 years now and won't flower without it at this point. I originally used it to increase yield with the longer light schedule but also noticed a shorter flower time. I use it during the entire flower cycle with a 12/12 cycle at the beginning and end of flower and 13.5/10.5 in between.
I get a noticeable bump in yield and about 7 to 10 day shorter flower time depending on the strain.
Click to expand...
capn can you tell us again what coverage you use for your 730s (watts/SF). ive seen a wide range of recs
 
testiclees

testiclees

Well-Known Member
Im using 3500k, cxb3590 and 4k, v29, along with a 54w t5 that claims to supply 12w uvb.
(730nm bar in the works).
Breeder states 9-10 week strain. The cycle was 3 weeks 12/12, 3 weeks 13/11, 11.5 /12.5 to finish.

Is it always smart to hasten the flowering period? My favorite strains almost always have long flower periods.

3-2 sp 1.jpg 3-2 sp 2.jpg 3-2 SP.jpg
 
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captainmorgan

captainmorgan

Well-Known Member
BOBBY_G said:
capn can you tell us again what coverage you use for your 730s (watts/SF). ive seen a wide range of recs
Click to expand...
My first units that I bought were 10 watt floods and coverage was stated as 64 sq/ft, that's .15 watts per sq/ft. and the maker of the units told me his coverage estimate was conservative,a little goes a long way.
 
BOBBY_G

BOBBY_G

Well-Known Member
so lets for fun say that 0.5-1W/SF is more than adequate for our purposes and go with that. with the multichip emitters and low utility of this setup is cheap and easy to err on the conservative side
 
Symbolic

Symbolic

Member
captainmorgan said:
I've used 730nm as a phytochrome trigger for over 3 years now and won't flower without it at this point. I originally used it to increase yield with the longer light schedule but also noticed a shorter flower time. I use it during the entire flower cycle with a 12/12 cycle at the beginning and end of flower and 13.5/10.5 in between.
I get a noticeable bump in yield and about 7 to 10 day shorter flower time depending on the strain.
Click to expand...
U turn 730nm mins beofre lights out.. or at lights out.. and how long do u keep them on for?
 
Banana444

Banana444

Well-Known Member
I have noticed plants ripening faster under rw150. Seems like its the 620-630nm reds from the xpes. It really brings out the colors of these plants. I know cobs are far cheaper and more efficient than running monos but im tempted to build a xpe2 red bar, maybe a pontoon for the indagro420 instead of shelling out ~700$ for one.
 
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