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I know people who use CLW lights. They're good fixtures but if you want tune-able spectrum and you don't want to spend a grand, you can do what I did. I purchased my 440 blues and my 660 reds from Mars Hydro and my 730 reds from Spiderfarmer and then plugged them all into their own smart outlet timers. Using reds and blues are an excellent way to use crop steering because these colors have a strong impact on plant morphology. Here's a picture of my lights:Hey does nobody use anything but SF and HLG ? wanna to get a bar light but for my CLW spectra max its a grand + looking for dimmable and control of red and blue spectrum but not necessarily a must.
Wow !! That was long winded but informative article. I am contemplating maybe just picking up a board and diodes and break out the soldering iron.I know people who use CLW lights. They're good fixtures but if you want tune-able spectrum and you don't want to spend a grand, you can do what I did. I purchased my 440 blues and my 660 reds from Mars Hydro and my 730 reds from Spiderfarmer and then plugged them all into their own smart outlet timers. Using reds and blues are an excellent way to use crop steering because these colors have a strong impact on plant morphology. Here's a picture of my lights:
View attachment 2469798
Here's a report I wrote with the help of AI that covers my use with these lights over 2 different grows. I have a 3rd planned this fall to further my studies in light frequency steering.
Advanced Spectrum Manipulation in Cannabis Cultivation - Experimental Report
Executive Summary
This report documents a series of controlled experiments investigating the effects of targeted wavelength supplementation on cannabis plant architecture, yield, and quality characteristics. Through systematic manipulation of specific light spectrums (440nm blue, 660nm red, 730nm far-red), significant control over plant morphology and secondary metabolite production was achieved while maintaining craft-level flower quality.
Experimental Period
Duration: September 1, 2024 - June 4, 2025
Growing Space: 5' x 5' cultivation area
Experimental Runs: 2 completed, 1 planned
Run #1: Initial Red Spectrum Supplementation
Protocol
- Supplemental Lighting: 660nm red + 730nm far-red LEDs
- Timing: Synchronized with main lighting schedule (standard photoperiod)
- Duration: September 2024 - January 2025
Results
Plant Architecture:
- Significant stem elongation observed
- Increased internode spacing
Quality Characteristics:
- Heavy trichome development ("heavily frosted")
- Abundant terpene production
- Craft-level flower quality achieved
Yield Impact:
- Reduced overall yield due to energy allocation toward stem development
- Loss of productive flower sites due to excessive stretch
Analysis
The constant supplementation of 660nm and 730nm wavelengths triggered phytochrome-mediated shade avoidance responses, resulting in beneficial stress that enhanced secondary metabolite production while compromising structural efficiency for yield optimization.
Run #2: Advanced Spectrum Timing Protocol
Protocol
Supplemental Wavelengths:
- 440nm blue
- 660nm red (increased intensity from Run #1)
- 730nm far-red (increased intensity from Run #1)
Timing Schedule:
- 440nm Blue: 18-hour photoperiod throughout vegetative stage and continued through first 14 days of 12/12, then discontinued
- 660nm Red: 10 minutes pre-light activation, full photoperiod, 10 minutes post-light extension
- 730nm Far-red: 30 minutes pre-light activation, OFF during main 12-hour photoperiod, 30 minutes post-light extension
Results
Vegetative Growth:
- Super lush, healthy plant appearance during vegetative stage
- Enhanced vigor from full spectrum supplementation
- Robust structural development
Plant Architecture:
- Complete elimination of stretch
- Extremely compact growth structure
- Tight internodal spacing maintained throughout flowering
Quality Characteristics:
- Maintained craft-level flower quality
- Excellent trichome development
- Superior terpene profiles preserved
Yield Performance:
- Total Harvest: 3+ pounds from 5' x 5' space
- Yield Limitation: Suboptimal canopy coverage due to excessive compaction
- Space Utilization: Underutilized growing area potential
Analysis
The extended blue light exposure throughout vegetative growth and into early flowering effectively locked in compact architecture, preventing any stretch response even after discontinuation at day 14 of flower. The full spectrum supplementation during vegetative growth (440nm + 660nm + 730nm) produced exceptionally vigorous and healthy plant development, creating an optimal foundation for flowering. While this solved the elongation issues from Run #1, it overcorrected and limited canopy development needed for maximum space utilization.
Planned Run #3: Optimized Dual-Phase Protocol
Hypothesis
Strategic timing of blue light supplementation can achieve optimal balance between canopy development and quality enhancement by targeting distinct physiological phases of flower development.
Proposed Protocol
Vegetative Stage:
- 440nm Blue: 18-hour photoperiod alongside main lighting
- 660nm Red: 18-hour photoperiod alongside main lighting
- 730nm Far-red: 18-hour photoperiod alongside main lighting
Phase 1: Structural Development (Week 1-3 of 12/12)
- 440nm Blue: OFF (allowing natural stretch for canopy fill)
- 660nm Red: 10 minutes pre-light activation, 10 minutes post-light extension
- 730nm Far-red: 30 minutes pre-light activation, OFF during main 12-hour photoperiod, 30 minutes post-light extension
- Main Lighting: 12/12 photoperiod
Phase 2: Flower Maturation (Week 3+ of 12/12)
- 440nm Blue: Resume 12/12 timing alongside main lighting (quality enhancement focus)
- 660nm Red: Continue 10 minutes pre-light, 10 minutes post-light timing
- 730nm Far-red: Continue 30 minutes pre-light, 30 minutes post-light timing
- Main Lighting: Continue 12/12 photoperiod
Expected Outcomes
- Canopy Development: Adequate stretch in weeks 1-3 for optimal space utilization
- Quality Enhancement:Blue light reintroduction during flower development to stimulate:
- Enhanced trichome production
- Improved terpene synthesis
- Increased flower density
- Yield Optimization: Balanced approach targeting both quantity and quality metrics
Key Findings and Principles
Spectrum-Specific Effects Documented
660nm Red:
- Primary photosynthetic enhancement
- Supports overall plant metabolism
- Effective as pre/post photoperiod extension
730nm Far-red:
- Controls stretch response via phytochrome system
- Timing-dependent effects on plant architecture
- Strategic scheduling prevents excessive elongation
440nm Blue:
- Powerful compaction tool
- Effects persist beyond exposure period
- Critical timing for balancing stretch vs. compaction
- Potential quality enhancement during flower maturation
Cultivation Philosophy
Light spectrum manipulation serves as a precision tool for "sculpting" plant architecture and metabolic responses. Each wavelength functions as a specific instrument requiring strategic application based on desired outcomes and growth phase requirements.
Prerequisites for Advanced Protocols
Successful implementation of complex spectrum manipulation requires:
- Mastery of fundamental growing techniques
- Consistent environmental control
- Systematic experimental approach
- Detailed documentation and analysis
Recommendations for Implementation
For Experienced Growers
- Begin with single-wavelength experiments before complex timing protocols
- Maintain detailed records of plant responses to timing changes
- Consider genetics-specific responses in protocol development
Critical Success Factors
- Environmental Stability: Maintain consistent temperature, humidity, and airflow
- Baseline Consistency: Ensure all other variables remain constant during experiments
- Timing Precision: Use programmable controllers for accurate spectrum scheduling
- Documentation: Record morphological changes, quality metrics, and yield data
Future Research Directions
- Strain-specific spectrum response profiles
- Integration with environmental control systems
- Long-term effects on plant stress and resilience
- Optimization of spectrum intensity levels
Conclusion
Advanced spectrum manipulation represents a powerful tool for optimizing cannabis cultivation outcomes. Through systematic experimentation, specific wavelengths can be strategically deployed to control plant architecture, enhance quality characteristics, and optimize space utilization. The key to success lies in understanding each spectrum's physiological effects and applying them with precise timing to achieve desired cultivation objectives.
The progression from basic supplementation (Run #1) through overcorrection (Run #2) to the planned optimization protocol (Run #3) demonstrates the iterative nature of developing effective cultivation techniques. This approach of controlled experimentation, detailed documentation, and systematic refinement provides a model for advancing cultivation practices beyond traditional methods.
Here's the last picture I took with all 9 plants involved in the 2nd grow. Shortly after it was taken, I began the harvest process.
View attachment 2469800
Interesting that you're using AI. I just started using Grok and chatGPT for on this topic a couple of weeks ago and I've found both to be helpful.I know people who use CLW lights. They're good fixtures but if you want tune-able spectrum and you don't want to spend a grand, you can do what I did. I purchased my 440 blues and my 660 reds from Mars Hydro and my 730 reds from Spiderfarmer and then plugged them all into their own smart outlet timers. Using reds and blues are an excellent way to use crop steering because these colors have a strong impact on plant morphology. Here's a picture of my lights:
View attachment 2469798
Here's a report I wrote with the help of AI that covers my use with these lights over 2 different grows. I have a 3rd planned this fall to further my studies in light frequency steering.
Advanced Spectrum Manipulation in Cannabis Cultivation - Experimental Report
Executive Summary
This report documents a series of controlled experiments investigating the effects of targeted wavelength supplementation on cannabis plant architecture, yield, and quality characteristics. Through systematic manipulation of specific light spectrums (440nm blue, 660nm red, 730nm far-red), significant control over plant morphology and secondary metabolite production was achieved while maintaining craft-level flower quality.
Experimental Period
Duration: September 1, 2024 - June 4, 2025
Growing Space: 5' x 5' cultivation area
Experimental Runs: 2 completed, 1 planned
Run #1: Initial Red Spectrum Supplementation
Protocol
- Supplemental Lighting: 660nm red + 730nm far-red LEDs
- Timing: Synchronized with main lighting schedule (standard photoperiod)
- Duration: September 2024 - January 2025
Results
Plant Architecture:
- Significant stem elongation observed
- Increased internode spacing
Quality Characteristics:
- Heavy trichome development ("heavily frosted")
- Abundant terpene production
- Craft-level flower quality achieved
Yield Impact:
- Reduced overall yield due to energy allocation toward stem development
- Loss of productive flower sites due to excessive stretch
Analysis
The constant supplementation of 660nm and 730nm wavelengths triggered phytochrome-mediated shade avoidance responses, resulting in beneficial stress that enhanced secondary metabolite production while compromising structural efficiency for yield optimization.
Run #2: Advanced Spectrum Timing Protocol
Protocol
Supplemental Wavelengths:
- 440nm blue
- 660nm red (increased intensity from Run #1)
- 730nm far-red (increased intensity from Run #1)
Timing Schedule:
- 440nm Blue: 18-hour photoperiod throughout vegetative stage and continued through first 14 days of 12/12, then discontinued
- 660nm Red: 10 minutes pre-light activation, full photoperiod, 10 minutes post-light extension
- 730nm Far-red: 30 minutes pre-light activation, OFF during main 12-hour photoperiod, 30 minutes post-light extension
Results
Vegetative Growth:
- Super lush, healthy plant appearance during vegetative stage
- Enhanced vigor from full spectrum supplementation
- Robust structural development
Plant Architecture:
- Complete elimination of stretch
- Extremely compact growth structure
- Tight internodal spacing maintained throughout flowering
Quality Characteristics:
- Maintained craft-level flower quality
- Excellent trichome development
- Superior terpene profiles preserved
Yield Performance:
- Total Harvest: 3+ pounds from 5' x 5' space
- Yield Limitation: Suboptimal canopy coverage due to excessive compaction
- Space Utilization: Underutilized growing area potential
Analysis
The extended blue light exposure throughout vegetative growth and into early flowering effectively locked in compact architecture, preventing any stretch response even after discontinuation at day 14 of flower. The full spectrum supplementation during vegetative growth (440nm + 660nm + 730nm) produced exceptionally vigorous and healthy plant development, creating an optimal foundation for flowering. While this solved the elongation issues from Run #1, it overcorrected and limited canopy development needed for maximum space utilization.
Planned Run #3: Optimized Dual-Phase Protocol
Hypothesis
Strategic timing of blue light supplementation can achieve optimal balance between canopy development and quality enhancement by targeting distinct physiological phases of flower development.
Proposed Protocol
Vegetative Stage:
- 440nm Blue: 18-hour photoperiod alongside main lighting
- 660nm Red: 18-hour photoperiod alongside main lighting
- 730nm Far-red: 18-hour photoperiod alongside main lighting
Phase 1: Structural Development (Week 1-3 of 12/12)
- 440nm Blue: OFF (allowing natural stretch for canopy fill)
- 660nm Red: 10 minutes pre-light activation, 10 minutes post-light extension
- 730nm Far-red: 30 minutes pre-light activation, OFF during main 12-hour photoperiod, 30 minutes post-light extension
- Main Lighting: 12/12 photoperiod
Phase 2: Flower Maturation (Week 3+ of 12/12)
- 440nm Blue: Resume 12/12 timing alongside main lighting (quality enhancement focus)
- 660nm Red: Continue 10 minutes pre-light, 10 minutes post-light timing
- 730nm Far-red: Continue 30 minutes pre-light, 30 minutes post-light timing
- Main Lighting: Continue 12/12 photoperiod
Expected Outcomes
- Canopy Development: Adequate stretch in weeks 1-3 for optimal space utilization
- Quality Enhancement:Blue light reintroduction during flower development to stimulate:
- Enhanced trichome production
- Improved terpene synthesis
- Increased flower density
- Yield Optimization: Balanced approach targeting both quantity and quality metrics
Key Findings and Principles
Spectrum-Specific Effects Documented
660nm Red:
- Primary photosynthetic enhancement
- Supports overall plant metabolism
- Effective as pre/post photoperiod extension
730nm Far-red:
- Controls stretch response via phytochrome system
- Timing-dependent effects on plant architecture
- Strategic scheduling prevents excessive elongation
440nm Blue:
- Powerful compaction tool
- Effects persist beyond exposure period
- Critical timing for balancing stretch vs. compaction
- Potential quality enhancement during flower maturation
Cultivation Philosophy
Light spectrum manipulation serves as a precision tool for "sculpting" plant architecture and metabolic responses. Each wavelength functions as a specific instrument requiring strategic application based on desired outcomes and growth phase requirements.
Prerequisites for Advanced Protocols
Successful implementation of complex spectrum manipulation requires:
- Mastery of fundamental growing techniques
- Consistent environmental control
- Systematic experimental approach
- Detailed documentation and analysis
Recommendations for Implementation
For Experienced Growers
- Begin with single-wavelength experiments before complex timing protocols
- Maintain detailed records of plant responses to timing changes
- Consider genetics-specific responses in protocol development
Critical Success Factors
- Environmental Stability: Maintain consistent temperature, humidity, and airflow
- Baseline Consistency: Ensure all other variables remain constant during experiments
- Timing Precision: Use programmable controllers for accurate spectrum scheduling
- Documentation: Record morphological changes, quality metrics, and yield data
Future Research Directions
- Strain-specific spectrum response profiles
- Integration with environmental control systems
- Long-term effects on plant stress and resilience
- Optimization of spectrum intensity levels
Conclusion
Advanced spectrum manipulation represents a powerful tool for optimizing cannabis cultivation outcomes. Through systematic experimentation, specific wavelengths can be strategically deployed to control plant architecture, enhance quality characteristics, and optimize space utilization. The key to success lies in understanding each spectrum's physiological effects and applying them with precise timing to achieve desired cultivation objectives.
The progression from basic supplementation (Run #1) through overcorrection (Run #2) to the planned optimization protocol (Run #3) demonstrates the iterative nature of developing effective cultivation techniques. This approach of controlled experimentation, detailed documentation, and systematic refinement provides a model for advancing cultivation practices beyond traditional methods.
Here's the last picture I took with all 9 plants involved in the 2nd grow. Shortly after it was taken, I began the harvest process.
View attachment 2469800
Only one thing ... AI didn't tell me anything. I told AI what I was doing and why I went with those timings. AI wrote the report based on my findings which actually pretty closely mirrors what Dr Bugbee has said.Interesting that you're using AI. I just started using Grok and chatGPT for on this topic a couple of weeks ago and I've found both to be helpful.
Having said that, it's good to get them to cite the sources for their analyses because they only "know" what's fed into them. My experience has been at they will regurgitate the "conventional wisdom" from time to time.
Even when they cite sources, read the cites thoroughly. I've seen chat make an assertion, it was about autoflowers, and the topic wasn't even referenced in some of the sources much less discussed for autos.
In terms of the advice that's been given, the information presented is well known but it's nicely, and convincingly written.
This is a screenshot I captured on 5/1/22 from a Bugbee video that was a few years old at the time. The picture is of Paul Kasuma who hasn't been in the Bugbee orbit for some time.
View attachment 2475268
If you check out pretty much any of the Bugbee videos on plant lighting, that's the gist of his research.
As you've said, the spectrum has an influence on morphology but blue and far red are the only ones that are major players. Red diodes, 660nm, are a staple in "white" LED's because they're electrically efficient so they deliver photons with a relatively low power input.
Newer lights are increasing the amount of 730nm, and I suspect one reason is to offset what "the Bugbee Boys" (Westmoreland, Bugbee, and Kusuma) described in their 2021 paper "Cannabis lighting: Decreasing blue photon fraction increases yield but efficacy is more important for cost effective production of cannabinoids".
What caught my eye is that the AI bot is recommending 660 only for a short duration. I use the R80's with my Growcraft X3 flower light in my 2' x 4' tent. My reason for this is twofold-the Growcraft is an older light, designed in 2019, and, while its PPFD map was excellent "back in the day", my preference is for a more even light cast. The second reason was that the R80's significantly increase the percentage of 660 in the spectrum, even though it is the "flower" version of the Growcraft (I use their veg light in veg). When I bought them last November, that was a theory on my part. In the past few weeks, I've used chatGPT and Grok for this type of analysis and my approach has proven valid.
When reading the AI advice that you've posted, I was surprised that the bot was recommending that they only be used per and post lights out. Firing up 660 before lights is just turning the lights on earlier because 660 is an inherent part of PAR (vs 730 which is not in PAR but Bugbee has been pushing to get ePAR as a NIST standard and hasn't been successful). There is dissuasion that 660 post lights out can help with the Emerson effect but I don' know that's been demonstrated to be of value at higher PPFD's.
I uploaded a series of files to Grok and asked it to analyze and discuss some different scenarios. Per the discussion at the link, the files were the PPFD map and spectrum for the R80 and for the FCE-6500 (Mars uses the same spectrum for all of their big lights).
The discussion is at this link.
I'd be interested in your comments on that discussion. Also, why did you go with the Spider R80's instead of the supplemental lights from Mars?
Vipraspectre, mars hydro, phlizon or however you spell it, so many others, literally every brand is used on hereHey does nobody use anything but SF and HLG ? wanna to get a bar light but for my CLW spectra max its a grand + looking for dimmable and control of red and blue spectrum but not necessarily a must.
I'm happy with all my lights. I have 2 Grower's Choice ROI E720's, a 630 watt Nanolux folding bar light fixture. 4 Kingbrite quantum boards, 2 sets of AC Infinity Ion Beams, plus the Mars and Spiderfarmer supplemental lighting. All of it works great! However, if I were to do it all over again, I would have saved a few dollars by purchasing something from Phlizon/Viparspectra/Spiderfarmer etc instead of the Grower's Choice Fixture. It's a high quality fixture at a higher price point. Even the CLW fixtures are selling today for less than I paid for those Grower's Choice 5 years ago.Vipraspectre, mars hydro, phlizon or however you spell it, so many others, literally every brand is used on here
I am using a spider farmer G3000 300 watt bar light and im happy with it. I like vipraspectre as well, but ive never used their bar style lights![]()
I use one of their UVb fixtures for veg and flower but the other ones are way out of my price range.
I'm experimenting using it at the very end of the dark period by itself as a preventative measure against PM. So far so good![]()
They're plenty strong enough for my small 2 by 4 tent. If you're not careful you can burn the living crap out of the plants. I fried a 3 by 3 pretty good too once. Mine get 20-25 min a day spread out in 4 intervals.I expect that UVB does have an effect but the limits are on the strength of the florescent tube used in the CLW UVB fixture. Next generation will likely be LEDs and will likely have more output. Once I find something higher in output, I'll pull the plug and recircle back to add the UVB into the mix.
They're plenty strong enough for my small 2 by 4 tent. If you're not careful you can burn the living crap out of the plants. I fried a 3 by 3 pretty good too once. Mine get 20-25 min a day spread out in 4 intervals.
I think the recommendations to add them at the end of flower are wrong. They have to be run basically the whole grow otherwise there's not enough time for a sufficient response from the plants. This is one of the very few bro science hills that I stand on actually because I've seen it over and over again in my grows.
I also think the deep blue keeps my girls a bit shorter. They literally grow away from this light lol![]()
Only one thing ... AI didn't tell me anything. I told AI what I was doing and why I went with those timings. AI wrote the report based on my findings which actually pretty closely mirrors what Dr Bugbee has said.
I'm using the 730 nm wavelength to mimic the Emerson effect which is why they aren't on during the whole lights on period. I went with the Spiderfarmers over the Mars because when I ordered them, Mars was out of the ones I wanted. The grow was already started and I wanted more 730 nm reds in the mix. If Mars had them in stock at the time I ordered the 440 nm blues and the 660 nm reds, I would have ordered the 730 nm as well. If you were thinking there was another reason, there wasn't ... it was all based on availability. My whole premise is you can use these colors blues/reds/far reds to steer your crop.
I'll be starting trial #3 next month sometime. I'll be running the following strains:
View attachment 2475352
Edit: In a previous run, I found no noticeable difference running CLW UVB's (2 sets in a 5 x 5). I believe UVB has an effect if you have enough UVB in the mix ... but I don't think the UVB fixtures from CLW are powerful enough to trigger the effect. I'm hoping to test out some next generation UVB at some point.
Neither link worked for me. Do you have a source for UVB LEDs?
Plants look healthy ... These are the outdoor shed run, correct?
Correct! But we had a male so we're down to three.Plants look healthy ... These are the outdoor shed run, correct?
Sorry, the company is solacure. Lookup: "solacure busting myths" and go from there. The article is pretty good. Supposedly their UVB bulbs are the real deal.Neither link worked for me. Do you have a source for UVB LEDs?
Those sound better than CLW for sure. First off, 40 watts instead of 25. Second, the fixtures/bulbs are a full 4' in length. That's a plus for sure. So 2 would give me 30 more watts than 2 CLW fixtures. That would essentially be like having 3 of the CLW fixtures in the same 5 x 5. Wave length is the full 280nm to 320 nm UVB spectrum. The only thing I don't like about them is they are still a florescent tube (fragile glass) but I do agree these would be better suited to testing UVB effects on cannabis. Thanks for the tip ... I'm going to think about it!Sorry, the company is solacure. Lookup: "solacure busting myths" and go from there. The article is pretty good. Supposedly their UVB bulbs are the real deal.
Don't use the highlight text above just type in the keywords
The UVB fixtures I use don't live up to all the hype, but, there is a noticeable increase in sunscreen (trichome) production on my plants.