Does hydroponics increase quality that much ?

[Absorber]

Great video and setup chief

Thanks for the kind words

 

[xox]

i think the biggest factor when it comes to quality assuming all things are equal between each grow comes down to genetics. although i also believe you can get some slight increases in quality as far as flower density and yield goes with a proper co2 enriched room and proper light intensity measured with a full spectrum meter but at that point your splitting hairs.

 

[formularacer]

I read most of this and still have one question.
Is hydro better than growing outside?

 

[Delps8]

i think the biggest factor when it comes to quality assuming all things are equal between each grow comes down to genetics. although i also believe you can get some slight increases in quality as far as flower density and yield goes with a proper co2 enriched room and proper light intensity measured with a full spectrum meter but at that point your splitting hairs.

This is from a Bugbee/Westmoreland video from a few years ago. As DLI increase, metabolites changed but there was also a change in the size of the colas.

Granted, no one grows at 10DLI but the different between 30 and 50 is germane.

And if you can increase CO2 levels to 1200, you should see a 30% increase in yield. If only you could run CO2 in a tent!

 

[Delps8]

I read most of this and still have one question.
Is hydro better than growing outside?

Those are different parts of the grow equation.

Hydro is a way of supporting the factors that comprise the root zone. "growing outdoors" encompasses the "above ground" parts of the grow environment.

The biggest advantage of growing indoors is the opportunity to control every aspect of the grow environment. It's smaller scale and has the potential for higher quality but is significantly more expensive. Outdoors is…dirt cheap but the potential for a poor outcome is far greater.

 

[formularacer]

Those are different parts of the grow equation.

Hydro is a way of supporting the factors that comprise the root zone. "growing outdoors" encompasses the "above ground" parts of the grow environment.

The biggest advantage of growing indoors is the opportunity to control every aspect of the grow environment. It's smaller scale and has the potential for higher quality but is significantly more expensive. Outdoors is…dirt cheap but the potential for a poor outcome is far greater.

View attachment 5440456

Reasonable answer thank you

I start them indoor then let them run wild outdoors.
My 2 cents is it is not much cheaper hundreds of dollars in soil additives, ladybugs every week the list goes on.
Plus based on scale it is more work and you can have loss but I think if you get most of it dialed in you can have a great product in volume.

 

[Greengrouch]

You’ll get faster growth and bigger yields I flipped these to flower a week ago and only vegged for for 2

I use the stirponic kit from pahydroponics.com not to priceey

 

[ttystikk]

You’ll get faster growth and bigger yields I flipped these to flower a week ago and only vegged for for 2

I use the stirponic kit from pahydroponics.com not to priceeyView attachment 5440747View attachment 5440748

"Stirponics"? What's different about that from regular RDWC?

 

[Mumbeltypeg]

Net photosynthesis is the amount of glucose generated by a leaf during the process of photosynthesis minus the glucose used by the leaf during the process of photosynthesis.

The Chandra paper was a big deal for a variety of reasons and one of the impacts of the paper is the data presented in the paper/displayed in the chart indicate that there's a rapid decrease in the value of increasing light levels on a cannabis grow. Put another way, the rapid falloff in net P as light levels increase was the law of diminishing returns showing that there was rapidly decreasing benefit in growing cannabis at high light levels.

Reading through the details of the Chandra paper revealed that the measurements of photosynthetic output were taken by putting leaves in a device about the size of a shoe box and measuring the output. That struck me as odd - was it valid to extrapolate the out of of glucose from a few leaves to the yield of a cannabis plant?

My response was "I'm not harvesting net photosynthesis" and I looked around for research that dealt with yield rather than net P from a few leaves in a box.

What was playing in the back of my mind was that emphasis that Bugbee was putting on growing cannabis under high light levels. Bugbee never put forward yield data but everything he talked about was growing at four digit levels (albeit that was in CO2). And I came across the description somewhere (to this day, I can't cite the source) that the light saturation point for cannabis is "800 to 10000µmols, depending on the strain.".

It wasn't until I found "Frontiers in Plant Science - Yield, Potency, and Photosynthesis in Increasing Light Levels" (attached) that, pardon the pun, the light went on. The authors, one of whom is Zheng who is a former Bugbee student IIRC, tackles the issue head on. The key phrase is "plasticity". Search the PDF for that word and that part of the text (one of the many highlights) states that net P of a few leaves cannot be taken as a proxy because cannabis has tremendous "plasticity" when it comes to yield and increasing light levels.

A step aside - essentially all light recommendations "on the internet" appear to rest on the results of the light levels in the Chandra paper. No doubt many of them have never heard of the Chandra paper but the light levels that are recommended are, my word, "modest". The lights at Migro appear to be specifically designed to work at those levels. If you look at the Migro lights, the drivers are lower powered than many of the competing products and if you read the Migro blog, you'll see that Shane stays well away from 1kµmol.

Another source that deserves mention is the data presented in the charts at growlightmeter.com. When I emailed the programmer a few years ago, asking for sources for their recommended light levels, I was told to check for footnotes on the bottom of the page where the data were presented. At the time, there were none and I haven't bothered to check back since for the reason that the research data that's been published is overwhelmingly different than what growlightmeter.com presents on their site.

Back on the research track - the other attached papers support the findings in the Frontiers paper. Their approaches are different but, overall, they buttress the assertion that cannabis yield tends to increase a light levels increase, as long as light is the limiting factor.

The most recent addition to the canon is the work done by Mitch Westmorelan, who is (was?) a PhD candidate under Bugbee. A year ago, he released a pair of videos in which he discusses some of the research that he conducted for his thesis. He makes it quite clear that his research indicates that cannabis yield increases as light levels increase.

This video is one of the two longer ones but he's done shorter, interview-length videos with Shane (Migro) on different topics. The topics are similar but Westmoreland adds little tidbits here and there.

Somewhat of a long response, eh?

The shorter version:

The table below is from the cited paper. If you plot the curve, you'll see that the law of diminishing returns is quite evident but the curve rolls off at a much slower rate than the curve of net P in the Chandra paper.

View attachment 5439959

Clearly, I'm an enthusiastic supporter of growing using high light and I do follow that practice with my grows. I run my grows as close as I can get to 1kµmol on average, or higher, and have no complaints about the results.

Growers have commented that high light tends to reduce the quality of the crop but the research doesn't support that. My belief is that Westmoreland addresses the issue, based on his research in 2021 and subsequent years, which he discusses in the videos I've cited.

The issue with reduced quality that some growers (including me) experience when cannabis is grown under high light is not due to high light levels but is a function of not keeping the temperature of the flower tops to <=78°. The graphic below is from his recent video and it substantiates the results that he reported in his 2021 video.

View attachment 5439960

Grow lighting for cannabis is a very deep topic but the Westmoreland videos, at only 50± minutes in length, are an excellent summary of the body of research that I've been able to dig up.

Love this Delps.. nice write up. So your dropping temps at late flower now I assume? And are you lowering light ppfd and co2 at the same time, or holding them steady?

 

[Delps8]

"Stirponics"? What's different about that from regular RDWC?

Stirpopnics is RDWC with 5 gallons buckets where water comes in at the bottom of the bucket. PA Hydro also sells Fallponics with 8 and 13 gallon "buckets" where the nutrient solution comes in at the top of the bucket. They're both RDWC because they have a res.

 

[Delps8]

Love this Delps.. nice write up. So your dropping temps at late flower now I assume? And are you lowering light ppfd and co2 at the same time, or holding them steady?

I'm not dropping PPFD. Someone raised the issue that Westmoreland had discussed that in his video and I went back and listened to the vid again (at 1.5 speed, granted) and didn't hear him say that. My current grow has been a bit of a PITA because, unlike my previous three or four grows in which I grew only one plant, I decided "Well, I'll try two" and it wasn't worked out too well.

I've seen this pattern in past grows; I refer to them as "Twins grows", named after the movie starring deVito and Schwarzenegger. Donna and Erica were Orginal. Glue seeds from Nirvana and were the best two of three seedlings. Early in veg, Donna was clearly larger than Erica and the difference has continued to increase.

About two weeks ago, I gave up on canting the main light and I moved in a Vipar XS1500 for Erica. Donna's canopy has become pretty uneven so I've had to resort to putting "lamp shades" around the light bars. A "lamp shade" is a piece of bond paper, wrapped around the light bar, fixed with Gorilla tape. I slide them along the light bar, as needed to control PPFD. Hang height in the photo below is about 12" which a recent increase but I need to do that to try and get the lightcast evened out.




My PPFD readings from yesterday include only the colas. The rest of the canopy is, unfortunately, down in the 700's.



vs PPDF from about a week ago



I spent a fair amount of time looking for a new light (my flower light is a model year 2020 Growcraft). The Gen 1 Spider G/SE4500 was my weapon of choice, with it 430 watt driver. Before I pulled the trigger on it, I bought and tested the new MarsSP3000R. That gives out a huge amount of 660 light (>90% I'd say) but I couldn't overcome the PPFD map and the heat output was prodigious.

By the time I returned the Mars, Spider pulled the high wattage 4500's off the market and released gelded versions with a 320 watt driver. "Damn you Murphy, you've won again!". But that wasn't the case.

After eschewing "add on lights", due to there being no PPFD data, I resisted the issue and, as of last week, shoehorned a pair of Spider R80's in the tent. They're an absolute bargain. I'm getting 300±µmol of 660nm light for 80 watts. The increased PPFD allows me to turn the dimmer on my Growcraft down from 300-330 watts to 170 watts and I'm getting very similar PPFD's on the plant.

The drop in wattage on the Growcraft looks to have dropped ambient temps by a couple of degrees. For my current grow, I'd like to have that heat back because we're having a cold Fall here in Souther Commiefornia so temps in my garage are down a bit.

11//22/24—Yikes! (and, yeh, I'm old - 68 years worth)


Daytime ambient temps are <=82 now and temps at the tops of the colas are 75±°.

Uneven canopy.


In this photo of Govee sensors, 2 and 4 are in the Koolatron cannabis fridge that I use while 1 and 3 are hanging in the canopy and 5 is the sensor that's visible in the photo at the back of the plant (the sensor on the right is a PulseZero).

While the temp in the plant (#1 and #3) are below 75, which is where bud rot likes it, RH is low enough to keep bud rot at bay. #5 is right at the top of the canopy so 76 and 62 should be good to hold of bud rot. I lost a very nice plant to bud rot a year ago and don't want have that happen again.



Oh, you wanted an answer to your question!

As a result of switching to the R80's, there's less heat in the tent. Ambient temp is down and flower tops are 75° so I'm in good shape for temps.

It takes some time to futz with the lamps shades, the dimmer %, and the hang height (the light is canted, higher in the back) so PPFD is pretty much the same.

CO2 - I'm in a tent so it's ambient CO2.


[edit]
PPFD on Erica is pretty good but there aren't really colas, per se. Buds are forming but they're even with the canopy. These are the PPFD values from yesterday:

 

[Greengrouch]

"Stirponics"? What's different about that from regular RDWC?

Branding lol. It’s a very basic budget rdwc setup that you buy as a kit. Only 1” tubes though so you gotta watch out for root clogs

 

[ttystikk]

Branding lol. It’s a very basic budget rdwc setup that you buy as a kit. Only 1” tubes though so you gotta watch out for root clogs

My 27 gallon tuffbox tubs have 4 x 1" bulkhead fittings and yes, I do have to reach down and pull roots out of them once or twice a run.

 

[Has]

When growing, DWC roots often twist into a rope. This is due to a slight asymmetry in air flow and slow rotation of water in the tank. Perhaps such twisting does not greatly affect the formation of nutrients, but is definitely bad for the respiration of the roots, since the penetration of air bubbles into the centers of such a rope is very limited. To prevent the roots from tangling, a mounted frame can be attached to the bottom of the pot. The roots can be tied or threaded through the mesh.

 

[DeadHeadX]

Reasonable answer thank you

I start them indoor then let them run wild outdoors.
My 2 cents is it is not much cheaper hundreds of dollars in soil additives, ladybugs every week the list goes on.
Plus based on scale it is more work and you can have loss but I think if you get most of it dialed in you can have a great product in volume.

I know this is a thread about hydroponics and other methods, but reading this stuff always makes me glad I grow in soil. Different strokes…I like to keep things simple. It’s definitely not “hundreds of dollars” per grow. I splurge on the fox farm soil at about $35-$45 a grow (filling four, five gallon containers). I’ve been using Dr. Earth dry amendments exclusively for a couple grows now. That stuff is cheap. A $20 bag is good for multiple grows. Let’s say $15 a grow in amendments, though likely not that much. So I’m in under $75-100 (plus seeds and electric) per grow. Soil can be done cheap and simple with nice success. Just harvested a plant for around 135 grams in a 95 day grow. No testing anything. No machinery needed beyond lights and fans. Another coming down in a week or two. Some like the complexity, others like the simplicity, I guess. There are some pests, but no testing of water, cleaning reservoirs, rotting roots, clogged pumps, etc…

 

[formularacer]

I know this is a thread about hydroponics and other methods, but reading this stuff always makes me glad I grow in soil. Different strokes…I like to keep things simple. It’s definitely not “hundreds of dollars” per grow. I splurge on the fox farm soil at about $35-$45 a grow (filling four, five gallon containers). I’ve been using Dr. Earth dry amendments exclusively for a couple grows now. That stuff is cheap. A $20 bag is good for multiple grows. Let’s say $15 a grow in amendments, though likely not that much. So I’m in under $75-100 (plus seeds and electric) per grow. Soil can be done cheap and simple with nice success. Just harvested a plant for around 135 grams in a 95 day grow. No testing anything. No machinery needed beyond lights and fans. Another coming down in a week or two. Some like the complexity, others like the simplicity, I guess. There are some pests, but no testing of water, cleaning reservoirs, rotting roots, clogged pumps, etc…

Maybe you don't spend that much. So far this fall I have tossed 20 bags of composted manure bag of lobster chips and bag of chicken shit about 90$.
Then a container of ladybugs is 10 and maybe 15 times last season I tossed them so that is 150 and the list grows. Spent 60 on wood support 14 foot tall plants need some. Another 20 on netting and fishing line.

 

[ttystikk]

When growing, DWC roots often twist into a rope. This is due to a slight asymmetry in air flow and slow rotation of water in the tank. Perhaps such twisting does not greatly affect the formation of nutrients, but is definitely bad for the respiration of the roots, since the penetration of air bubbles into the centers of such a rope is very limited. To prevent the roots from tangling, a mounted frame can be attached to the bottom of the pot. The roots can be tied or threaded through the mesh.
View attachment 5441566

Is this one of the "stir ponics" RDWC? How does the water enter the bucket with the roots?

 

[Greengrouch]

Is this one of the "stir ponics" RDWC? How does the water enter the bucket with the roots?

There’s a small pump in the reservoir that pushes water through, the cloggings only a minor easily corrected inconvenience and mostly avoidable if you don’t grow em to big.

 

[ttystikk]

Yeah, fuck that not growing big bullshit! LOL

There’s a small pump in the reservoir that pushes water through, the cloggings only a minor easily corrected inconvenience and mostly avoidable if you don’t grow em to big.

I use one pump in the control bucket of my RDWC. It's connected to a manifold that delivers water to an elbow fitting in the lid of each of the 27 gallon tuff boxes, where the nutrient water splashes down, breaking surface tension, churning, agitating and aerating the water in the tub. The only downside is that indeed the roots do tend to get pulled into the drain fittings at the bottom where the water returns to the control bucket.

That one pump can service up to a dozen tubs, no air pump or stones necessary!

 

[Greengrouch]

Yeah, fuck that not growing big bullshit! LOL



I use one pump in the control bucket of my RDWC. It's connected to a manifold that delivers water to an elbow fitting in the lid of each of the 27 gallon tuff boxes, where the nutrient water splashes down, breaking surface tension, churning, agitating and aerating the water in the tub. The only downside is that indeed the roots do tend to get pulled into the drain fittings at the bottom where the water returns to the control bucket.

That one pump can service up to a dozen tubs, no air pump or stones necessary!

Even when you don’t grow em big they’re still big lol did a 2ish week veg on these and my 2x4 is packed, they’re near as tall as me with a shit load of lateral branching and a pretty even canopy