Too much light = reduced flavour?

[Andy]

Hi all,

I've been growing successfully for years & get a consistent 1g per watt. However, I use a lot of light intensity - about 1000W of HPS lighting per square meter, with no CO2 enrichment. I have a lot of extraction power and the canopy is kept cool enough (no higher than 27 degrees. The buds look great when harvested.

However, I'm on a mission to increase flavour - is it possible that such a high light intensity could be reducing the flavour/terpene potential of the crop, even though temperatures are fine?

 

[MIMedGrower]

Hi all,

I've been growing successfully for years & get a consistent 1g per watt. However, I use a lot of light intensity - about 1000W of HPS lighting per square meter, with no CO2 enrichment. I have a lot of extraction power and the canopy is kept cool enough (no higher than 27 degrees. The buds look great when harvested.

However, I'm on a mission to increase flavour - is it possible that such a high light intensity could be reducing the flavour/terpene potential of the crop, even though temperatures are fine?

Yes! I have learned to move the hps lamps away a few inches during ripening. Definitely protects terpenes and even canabanoids from degradation.

Still think its the heat of the lamp causing the degradation. My canopy meter never goes beyond 77 farenheight but the surface temp may be higher under a streetlamp for 12 hours at a time.

 

[One drop]

Hi I did have a run where I had a 600 Hps in my 3x3 x6 tent and a 400 Hps in the other same size tent , both at 36” above canopy both crops NL#5 600w tent flavour was half as good as the 400 w I got another 400w light and retired to 600 w , so yes I think yes it dose play a big part along with the heat as stated above .

 

[MIMedGrower]

Hi I did have a run where I had a 600 Hps in my 3x3 x6 tent and a 400 Hps in the other same size tent , both at 36” above canopy both crops NL#5 600w tent flavour was half as good as the 400 w I got another 400w light and retired to 600 w , so yes I think yes it dose play a big part along with the heat as stated above .

That sounds about right if you dont “work” the more powerful light. Not much talk about this but more light intensity can mean more potency along with yield. My weed has been stronger under 2 600’s than it was under only one. I adjust the height of my plants under the fixed lamps often.

 

[One drop]

That sounds about right if you dont “work” the more powerful light. Not much talk about this but more light intensity can mean more potency along with yield. My weed has been stronger under 2 600’s than it was under only one. I adjust the height of my plants under the fixed lamps often.

Yep good idea I’m thinking of stripping down the 2 tents and building out a room in the shed so I can just run the 600w I’ve got 2 m wide x 1 m deep x 1.9 m High the 600 would look after that size space with 6 plants under it . Od .

 

[Aqua Man]

I found running higher sulfur the last few weeks to help with terps and flavonoids this round I'm going 48 dark at the end on the grow. Haven't thrown into the whole grow yet but thinking about it

I also feel heat is likely the number 1 culprit

 

[MIMedGrower]

Yep good idea I’m thinking of stripping down the 2 tents and building out a room in the shed so I can just run the 600w I’ve got 2 m wide x 1 m deep x 1.9 m High the 600 would look after that size space with 6 plants under it . Od .

I use 2 600’s for that space with 6-7 plants. One will only flower 3.5’x3.5’ maybe 4x4 in a reflective tent to potential in my experience.

 

[MIMedGrower]

I found running higher sulfur the last few weeks to help with terps and flavonoids this round I'm going 48 dark at the end on the grow. Haven't thrown into the whole grow yet but thinking about it

I also feel heat is likely the number 1 culprit

My well water and ocean forest and pure blend pro had plenty of sulfer and the difference was still very apparent.

Now with less sulfer from pro mix and foliage pro i am getting even more smell and flavor and the last buds and ones growing are even more full of resin.

My well water has a few ppms of sulfer

 

[One drop]

I found running higher sulfur the last few weeks to help with terps and flavonoids this round I'm going 48 dark at the end on the grow.

I also feel heat is likely the number 1 culprit

Cool I noticed a little foxtailing on my NL #1 I had about 2” left to raise up the 400 w Hps so I’m at 39.5” above crop and heat has dissipated down to 28 deg c foxtailing has seemed to back off , I’m so close to harvest I’ve even got my shade cloth ready for the last week or so of flushing don’t want all this hard work go to waste flavour wise . Od .

 

[One drop]

I use 2 600’s for that space with 6-7 plants. One will only flower 3.5’x3.5’ maybe 4x4 in a reflective tent to potential in my experience.

I could run the 400 together then have a better spread of light over 6 plants is that a better way for me to go . .

 

[MIMedGrower]

Cool I noticed a little foxtailing on my NL #1 I had about 2” left to raise up the 400 w Hps so I’m at 39.5” above crop and heat has dissipated down to 28 deg c foxtailing has seemed to back off , I’m so close to harvest I’ve even got my shade cloth ready for the last week or so of flushing don’t want all this hard work go to waste flavour wise . Od .

In glass enclosed air cooled reflectors i kept my 400 at about 12” and 14” for ripening. And 18” to 22” for my 600’s.

I use plenty of ventilation to maintain these heights. Even a few inches farther and yield and quality suffer a lot.

 

[MIMedGrower]

I could run the 400 together then have a better spread of light over 6 plants is that a better way for me to go . .

I think so. Multiple sources are always better for coverage and penetration.

 

[Aqua Man]

In glass enclosed air cooled reflectors i kept my 400 at about 12” and 14” for ripening. And 18” to 22” for my 600’s.

I use plenty of ventilation to maintain these heights. Even a few inches farther and yield and quality suffer a lot.

Cough* LED Cough*

 

[One drop]

In glass enclosed air cooled reflectors i kept my 400 at about 12” and 14” for ripening. And 18” to 22” for my 600’s.

I use plenty of ventilation to maintain these heights. Even a few inches farther and yield and quality suffer a lot.

Yield isn’t such a big thing with me and my wife I’m getting better yields with the old bat wing open light defuser keeping the height up at 36” and above if I can squeeze the light right to roof of tent then I have with light at 18” to 24” even with 2 fans tilted up across canopy . Od .

 

[Andy]

In glass enclosed air cooled reflectors i kept my 400 at about 12” and 14” for ripening. And 18” to 22” for my 600’s.

I use plenty of ventilation to maintain these heights. Even a few inches farther and yield and quality suffer a lot.

This sounds sensible, and would mean you can get the 600 to the right distance (18-22”) without that intense blanket of heat forming at canopy level. Others examples of 36” height for a 600 HPS would be too high for me as I don’t want to sacrifice yields.

But surely considering the confirmation from everyone here, the ovbious choice for me now is to go 100% LED no?

 

[Aqua Man]

This sounds sensible, and would mean you can get the 600 to the right distance (18-22”) without that intense blanket of heat forming at canopy level. Others examples of 36” height for a 600 HPS would be too high for me as I don’t want to sacrifice yields.

But surely considering the confirmation from everyone here, the ovbious choice for me now is to go 100% LED no?

There will be a learning curve to it but imo I think LED is at a place now where it is more than comparable. But it does provide it's challenges and does benefit from other supplemental lighting for spectrum imo. But so do other light sources.

 

[MIMedGrower]

This sounds sensible, and would mean you can get the 600 to the right distance (18-22”) without that intense blanket of heat forming at canopy level. Others examples of 36” height for a 600 HPS would be too high for me as I don’t want to sacrifice yields.

But surely considering the confirmation from everyone here, the ovbious choice for me now is to go 100% LED no?

I guess if you got the cash.

 

[Andy]

Hmm, definitely one to ponder and as you say, rather expensive!

 

[Aqua Man]

I guess if you got the cash.

Definitely a bigger upfront cost. Much bigger

 

[MIMedGrower]

Definitely a bigger upfront cost. Much bigger

Including all the money buying and running my reflectors and all the replacement bulbs for 5 years i still couldnt buy the gavita or growers choice strip lights i want to replace the hps with.

I could buy a chinese knockoff that is similar but it would still cost me $1200 after shipping to replace both lamps.

The common price argument for led does not work with only a few lights.