light spetrum and phenottpic display.

yggdrasil

New member
Most weed I grew before was under sodium light. When I switched in 50%cdm I was a bit surprised. My flowers were finished almost a week early.
And when I broke the room down, I had hardly any trash. Quality up but yield down.
Rather than switch back, I thought I'd try 100% cdm.
If I could plant about 50% denser, I might reach my expected yield , higher quality and bring it home early. Grm/kWh >grm/watt
Also understand some LED will foxtail and extend bloom times.
Anyone have any thoughts on how your plants react in spectrums not hps thanks.
All the best
 
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I have played around with almost every lighting configuration in the last 20 years and keep saying the same things. HPS make great yields period. MH alone make a great looking flower but just don't yield as well. The best lighting configuration you can use is a blend of HPS + MH.
By cdm I will assume you are talking ceramic metal halide. They are basically a MH which is superior in both spectrum and intensity by a small measure. (Although some of the latest gen quartz metal halides are very close) They do work better than MH alone but are best utilised in a blended scenario for best results. IME foxtailing is a result of environmental factors more than light quality. Eg extended photoperiod, too much N in the feed or excessive temperatures.
 
ProfessorJJ, thanks for that.
Yeah cmh was spellcheck error.
Have you grown in pure MH before?
Was the yield loss also matched by a shorter bloom?
Do you think if you jiggled it, density and pruning, you could use the variation in growing habit as an advantage I mean?
Thanks
 
I've only used the cmh one bloom.
They don't have as much 500-600nm as my old MH, and also a bit more efficient.
I can pair them with some DE hps , or even run DE MH, if the tech is so good now.
Really like the idea of running 6*315w verticals low over a bed with a rail, like an old fashion dot matrix. At $4k that's a lot to light a bed, if I'm just dropping yield though.
 
I have grown under CMH exclusively and whilst quality is excellent IME yield always suffers. I do think that a cmh spectrum hastens maturation, I have been using them exclusively for the last few weeks before harvest for exactly this reason. I feel there is something in it but I have really been nailing things lately (pat on my own back there) so can't be 100% but stories like yours give me confidence. One thing is for sure the plants look magnificent under a continuous spectrum. I think if you are resourceful you can turn almost anything to your advantage. If you are contemplating putting that sort of money into a light set up skip the cmh's and go straight for COB LED's....you will never look back.
 
noob question

I've been thinking lately the blue veg red bloom regime so clearly suits equitorial weed.
It controls the stretch then really allows them to puff out.
But not sure if mountain weed should be the same.
If it growing in a crack in a mountain, it might not even get noon light until the equinox. Mountains have strange light patterns.
The red veg night retard lower laterals, and give the plant stretch.
If you slightly open the bud would just protect mould.
After they stretched, bring them in quick with the blue.
With lollipops and working spectrum switch adjustments might go.
Current plant regime were created with a lot poorer choice, n poorer components.
No blue in the hps n poor efficiency in MH.
Just seems crazy, so this is theory only.
Or they just get thin twigs with hairs.
If it could work, probably would be working.

Focused more on light efficiency over plant quality. Probably pretty skinny bit stretchy flowers
 
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