Light levels at different stages of flower?

[SeaMaiden]

Right on!

I have also learned recently the hard way; keeping fresh bulbs is extremely important. It is not so much the lumens as it is the proper light spectrum. the multi spectrum hps are awesome. buying new high quality flower bulbs every 6 months is a must. every 4 months on the veg bulbs.

And THIS is what I've been wondering about with regard to vegetative and generative phases of growth. The thinking for me has been along the lines of how the quality of sunlight might change through the seasons, possibly starting off in early spring with more available light at the red end of the spectrum, moving toward blue as the season progresses, then back towards the red end as the earth tilts away yet again.

However, I have found nothing in science that speaks to this, nor do I really know *how* to look for papers or observations.

 

[EclipseFour20]

Not quite the silver bullet you want SeaMaiden...but this study shows increased watts does provide more grams of leaf and flower material--but most interesting is there seems to be NO CORRELATION between light intensity and actual cannabis potency.

https://docs.google.com/file/d/0ByW-RytTeYMQMTc3M2MxYzMtNjUxZi00ZGZhLTg0YWMtYjAzMzNjNGY5NDEw/edit?pli=1

I know there are various studies involving UV-b and UV-a rays and plant growth....so try including those terms in your search.

BTW...there might be other material in that particular library--so do browse.

Cheers!

 

[Crusader Rabbit]

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[localhero]

I'm at 5 weeks into flower and due to this being a new room and new genetics and some ac issues that kept me vegging for 2 extra weeks... I now have plants that are way too close to the lights even after scrogging the fuck out of them. anyways I started seeing the bleach effect taking place so i dimmed my 1000 w micromole ballasts to 750 on the systems that were too close. we will see what happens. the plants are close enough to the light source that theyre probably getting the same amount of lumens from 750 as they would have at 1000 with 2' distance from the canopies.

ps- yeah i am aware this is an old thread but its a good question from the op regardless

 

[Skunkenstein]

I ran dual 600's. For years..I switched to a Raptor Brand Air Cooled Hood and 1000watt Horti. And I'm way Happier!! Of subject slightly, but one of the BEST things I've ever done in my Plant growing Career is...wait for it...Switch Flowering Schedule to 11 on 13 off.Now before you get your Panties in a twist...Try it first and you will be Amazed! I will never go back to 12/12 ever. I believe this one simple technique works better than dimming and undimming lights several times during the Crop..Plus you save 1hr of electricity swell...Try it once, you'll be a true believer!!

 

[blastfrompast]

I do the 11/13 for my WW also....
I do the stretch and then bend and weave mostly. Trying 5 to a light this time vs 4.

Then some selective defoliation here and there to get a nice deep canopy and trim anything below my canopy off.

Seems to work.

As for light levels....It depends on the plant....I don't reduce the light levels on my sativa...or she will stretch to the ceiling....I gotta keep her tight.

WW I can let strech for for the rays a bit, if I need to fill the canopy a bit more to even it out.

 

[Skunkenstein]

The first time I ran 11/13, some of my plants responded so well I should have Vegged them up more. Under 11/13 plants are Hitting Apical Top bud in Approximately 8 days vs 13_14 under 12/12. It's a huge plant management tool,IMO.LUI,Sweet tooth,C-99 stop stretching almost immediately,which is great to see.The one plant that just kept on growing regardless was the Metal haze xC-99 from KOS seeds..Lots of piss n Vinegar in that F-1.I've got some Malawi and Mulanje gold Idlike to run..Gonna need a whole seperate Area for that disaster..haha, those Sativas can over take a grow room in a big Hurry..!!

 

[Swampdankv2]

Definitely interested in the 11/13 light schedule.

 

[G.Goo]

it is worth every penny to always run your shit at 1000 over 600. huge difference in yield. I know this for a fact. I have done side by sides. the bud also gets denser.

however you only need to run max light like ten hours a day. run half light fir the first and last hours.

at the end of flower it is important to run them at 1000 because it makes the plant use up more chlorophyll. so it flushes better and tastes better in final product

in veg it is important because it makes tighter internodes.

600 sucks. Even though a 1000 is only 400 more watts, it puts out way more than twice as many lumens.

digilux 600 95,000 lumens vs 145,000 lumens simple math says that's 45% less then 2x 600w hps 33% more then a 600w with a thousand

 

[Hash Zeppelin]

Last I checked, most 600's put out around 90k, while a 1000 did around 135k

Maybe it depends on bulb brand, or type of bulb. I was just going by my light meter when I made that determination. Maybe there is another factor I missed.

 

[Hash Zeppelin]

And THIS is what I've been wondering about with regard to vegetative and generative phases of growth. The thinking for me has been along the lines of how the quality of sunlight might change through the seasons, possibly starting off in early spring with more available light at the red end of the spectrum, moving toward blue as the season progresses, then back towards the red end as the earth tilts away yet again.

However, I have found nothing in science that speaks to this, nor do I really know *how* to look for papers or observations.

I have done a few experiments in small greenhouses in early spring in the East sf Bay Area. The results of that area turned out that it was best to wait until late may early June to put my plants outside. However this also maybe because I had a hillside blocking light for part of the day until that time of year. Also there is no rain then, so it made it easier to prevent PM with just proper spacing and plant pruning/ training.

 

[Corn Planter]

I have a full spectrum LED light that I can set blue, red, and white from 0 to 100%. The manufacture has suggested cutting back the red and increasing the blue the last two weeks of flower to increase quality of finished flower. Anyone heard or tried going with more blue light towards end of flower cycle?

 

[GYOweed]

I have a full spectrum LED light that I can set blue, red, and white from 0 to 100%. The manufacture has suggested cutting back the red and increasing the blue the last two weeks of flower to increase quality of finished flower. Anyone heard or tried going with more blue light towards end of flower cycle?

Extra Blue induces more thc i have to find the paper on it.

 

[GYOweed]

https://www.karger.com/article/FullText/489030
but not in total yield of cannabinoids. Plants under HPS treat- ment were taller and had more flower dry weight than those under treatments AP673L and NS1. Treatment NS1 had the highest CBG content. Treatments NS1 and AP673L had high- er CBD and THC concentrations than the HPS treatment. Re- sults were similar between experiments 1 and 2. Our results show that the plant morphology can be manipulated with the light spectrum. Furthermore, it is possible to affect the accumulation of different cannabinoids to increase the po- tential of medicinal grade cannabis. In conclusion, an opti- mized light spectrum improves the value and quality of can- nabis. Current LED technology showed significant differenc- es in growth habit and cannabinoid profile compared to the traditional HPS light source. Finally, no difference of flower- ing time was observed under different R:FR (i.e., the ratio be- tween red and far-red light). © 2018 The Author(s)

 

[Mars Hydro Led]

I have a full spectrum LED light that I can set blue, red, and white from 0 to 100%. The manufacture has suggested cutting back the red and increasing the blue the last two weeks of flower to increase quality of finished flower. Anyone heard or tried going with more blue light towards end of flower cycle?

Didn't have a chance to hear that before. Most of growers would like to add more red during flower stage to get better yield.

 

[GYOweed]

Didn't have a chance to hear that before. Most of growers would like to add more red during flower stage to get better yield.

There are many studies, this one has graphs and goes over the different profiles
https://journals.ashs.org/hortsci/view/journals/hortsci/53/11/article-p1593.xml

 

[Corn Planter]

Didn't have a chance to hear that before. Most of growers would like to add more red during flower stage to get better yield.

Yes flower for most of cycle under the red spectrum then the last 2 or 3 weeks switching back high blue intensity much like a veg spectrum.