Light levels at different stages of flower?

VerdantGreen · Mar 24, 2012

hi all, i was wondering if anyone had any papers or personal experience of using different light levels during flower to help Gram per watt efficiency (yes i know it isnt the best measure of efficiency but that's not what i want to discuss here)
Basically i would like to know at what point in flower is it important to have maximum light levels and at what point its not too detrimental to use lower levels.
eg i was thinking of lowest levels for late veg/early flower
highest levels for mid flower
and slightly lower for late flower till finish - which may help to preserve terpenes.

thanks

VG

Smelly_Cheese · Mar 24, 2012

yeah i was kind of wondering the same thing. My budget has changed. I have a 1000watt dimmable that im running a 600watt hps bulb in and im 5 days flower. I plan on running the 1000k bulb for weeks 3 thru 8 or 9 then back down to 600 for 9,10, and 11. Is this a good plan?

i was about to say fuck it and put in the 1000k bulb today but thats more ac and im pulling very hot air in from outside so its alot to cool.

VerdantGreen · Mar 24, 2012

ive heard of people using less light in early flower until the plants bud up, and ive heard of people raising the lights in late flower to reduce the heat radiation as the plants finish... but thats about it really. hopefully someone will have experience or info

VG

Smelly_Cheese · Mar 24, 2012

normally id just put in the bigger and say fuk it but im really doing my best to control cost. I do not sell and only grow for 2. I want a lb to last till late fall as i will shut down this year for summer. In summer outside temps over 90 everyday and i have to run a second ac. 2 ac's a 1k light on mover and fans and stuff were adding about $300 per month on summer months electric bill.

Grow_engineer · Mar 25, 2012

Smelly_Cheese said:
im pulling very hot air in from outside so its alot to cool.

Sounds like a sealed room yould be your way

I recently thought about a rotating System quite similar to anti´s colloseum, therefore i did want to change the places of the Plants so simulate a Cycle of Light that peaks in 2/3 of Flower, with reduced Power for the first 3 an the last 2 weeks counting on 12 Weeks in flower. (i hope this explanation makes sense in english

)

Hash Zeppelin · Mar 25, 2012

Smelly_Cheese said:
yeah i was kind of wondering the same thing. My budget has changed. I have a 1000watt dimmable that im running a 600watt hps bulb in and im 5 days flower. I plan on running the 1000k bulb for weeks 3 thru 8 or 9 then back down to 600 for 9,10, and 11. Is this a good plan?

i was about to say fuck it and put in the 1000k bulb today but thats more ac and im pulling very hot air in from outside so its alot to cool.

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.

BasementBreeder · Mar 26, 2012

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

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

Mate Dave · Mar 26, 2012

Its all down to experience of the plant in question in reality.

Some plants are more photosensitive than others Light leeks etc, I too have heard of the increase of light at the onset of bud,, it stops stretch that is all.

Its decreasing the food production capabilities of the mitochondria, Not low enough to promote week etiolated growth but less ability to produce reserves.

I doubt if it would increase brix in the plants,, also phytochromes and cryptochromes play a significant role in the floral expressions of a plant as much as exposure to photo period can.

At the end of the day thc is a protective sun screen for the lamina cuticle and also chloroplast and palisade mesophyll which contain the Carotenoids and Flavonoids that are responsible for growth.

Since the Thc is part of this area of the plant and that given a different spectrum of light will garner significantly better resin production if left late in flower as sinsemilla it seems that you could get the same kind of terpines etc but just less of them..

And less terpenes means a different kind of high as the taste makes the difference..

We should as Sam S...

187020 · Mar 26, 2012

Full tilt lighting has yielded best here...sequencing/dimming/decreasing light quantities always got me a bit less product. Peace

Smelly_Cheese · Mar 26, 2012

switched to 1000k bulb this morning. I just could think of not getting the maximum yield. I was able to spread everything out just a few more inches allowing better penatration.

Hash Zeppelin · Mar 26, 2012

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

I was a little off on the efficiency part. The quality 600 bulbs are putting out up to 90,000 lumens now, and the 1000s are doing 145,000. So just about double, not way more than double.

Hash Zeppelin · Mar 26, 2012

Mate Dave said:
Its all down to experience of the plant in question in reality. Some plants are more photosensitive than others Light leeks etc, I too have heard of the increase of light at the onset of bud,, it stops stretch that is all,,,,, Its de-creasing the food production capabilities of the mitochondria, Not enough to promote week etiolated growth but less ability to produce reserves,,, so I doubt if it would increase brix in the plants,, also phytochromes and cryptochromes play a significant role in the floral expressions of a plant as much as induction of photo period can, all in all thc is a protective sun screen for the lamina cuticle and also chloroplast and palisade mesophyll which contain the Carotenoids and Flavonoids that are responsible for growth, since the Thc is part of this area of the plant and that given different or full spectrums of light will garner significantly better resin production if left late in flower as sinsemilla it seems that you could get the same kind of terpines etc but just less of them.. And less terpenes means a different kind of high as the taste makes the difference.. We should as Sam S...

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.

VerdantGreen · Mar 29, 2012

thanks for the responses guys.

Cravenmore said:
Full tilt lighting has yielded best here...sequencing/dimming/decreasing light quantities always got me a bit less product. Peace

i presume you are talking about total yield rather than grams per watt?

VerdantGreen · Mar 29, 2012

Hash Zeppelin said:
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.

hi hash Z, i dont doubt that stronger lighting all through would yield more... but i was wondering about increasing gpw efficiency.

under LED's stretch isnt much of a problem so using less light in the first few weeks may be the best option. i see your point about stronger light helping to get the plants to yellow at the end.

thanks

VG

Harvest Time · Mar 29, 2012

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

this is what i was wondering.. i was doing and hour at the beginning and 2 at the end of the big lights off but the flouros on.. almost to start up and wind down the plants gentler and with less stress as natural light would with changing intensities during the day... i have always wondered if it would make a difference...someone do a side by side please..haha i wish i had the space ..i would...could be vital info in the furthering of our godly powers to control their enviroment as a whole...

CannabisFox · Mar 30, 2012

Hash Zeppelin said:
The quality 600 bulbs are putting out up to 90,000 lumens now, and the 1000s are doing 145,000. So just about double, not way more than double.

how long is it ago that 1000w are more efficient then 600w? like 30 years? ^^
600w hps' always were the most effizient ones

Bennyweed1 · Mar 30, 2012

I personally think the word lumen and PAR get tossed around much to frequently when we dont fully understand what they mean.

There is much more then growing a plant aside from 95,000 lumens. (600w)

We are not building Mustangs or GTRs, it isnt only about power output but rather usable energy and quality.

mad librettist · Mar 30, 2012

I have no cannabis specific info, but when it comes to veggies, the brighter the day you harvest, the less nitrate is left in the plant.

this is known because some people avoid nitrates in their diet as much as possible to lower cancer risk.

EclipseFour20 · Mar 30, 2012

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

But if you have the footprint...two 600's instead of a single 1000 is another alternative to consider. Two benefits I have noticed using tandem 600w lamps--

1. Less shadowing at the edges (no room for light mover setup for me)
2. Lamp can be closer to buds...or in my case, amazon buds can grow real close to the lamps without any "snap, crackle & pop".

Maybe if I had the ceiling space...tandem 1000w might nice, or even 1500w. But then that would require more AC usage and probably double my electric bill $$$; doubt my harvest would double in my 3.2kw flower (4-600w & 2-400w).

But yeah...600w is superior to a 400w, 1000w kicks ass over a 600w, and hard to beat the 1500w powerhouse; but if your buds are too far or too close--your buds ain't superior...just saying bigger does not always mean better.

Cheers!

supermanlives · Apr 1, 2012

2 600s kicks ass.

Light levels at different stages of flower?

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