All COB Users - Lettuce Grow Challenge!!
- Thread starter OneHitDone
- Start date
OneHitDone
Well-Known Member
Are you using strips in the veg tent or cobs?
robincnn
Well-Known Member
Strips in mini 1x1x2 tent
This is veg tent 2x2x4
Twin vero 29 on passive 140mm. Left 5000k 70 CRI, right 5700k 90 CRI. Thinking of adding a separator in middle. The Lamp has a 12v fan 120mm in middle under driver for airflow in tent.
It does limit the height. 4 cob setup would give more even coverage. This is fine too as I can slide the lamp front or back depending on where I want more intensity.
screw driver for dimming
This is veg tent 2x2x4
Twin vero 29 on passive 140mm. Left 5000k 70 CRI, right 5700k 90 CRI. Thinking of adding a separator in middle. The Lamp has a 12v fan 120mm in middle under driver for airflow in tent.
It does limit the height. 4 cob setup would give more even coverage. This is fine too as I can slide the lamp front or back depending on where I want more intensity.
screw driver for dimming
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thetr33man
Well-Known Member
What spectrum aquabars are you using? Ive got some growing lettuce and other houseplants plants. Im using 660 red, 2700k white, 6500k white repeating, seems to work well.
thetr33man
Well-Known Member
Heres some plants I have going under Cidly Aquabar LED's (above).
(below) Ive also got 2 recently set up Kratky units at home under a homemade COB bar, 6 x cxb2530 3000k 90cri @ 700mA dimmed significantly right now. Growing spinach, kale, and 3 varieties of lettuce, wasnt sure about plant spacing, these are 15 gallon totes. Also yellow lids let in some light, but not much at this intensity.
thetr33man
Well-Known Member
Nice setup!Strips in mini 1x1x2 tent
This is veg tent 2x2x4
Twin vero 29 on passive 140mm. Left 5000k 70 CRI, right 5700k 90 CRI. Thinking of adding a separator in middle. The Lamp has a 12v fan 120mm in middle under driver for airflow in tent.
View attachment 3666566
It does limit the height. 4 cob setup would give more even coverage. This is fine too as I can slide the lamp front or back depending on where I want more intensity.
screw driver for dimming
blowincherrypie
Well-Known Member
Yup.. Benefiting the world one cob at a time
SSGrower
Well-Known Member
So the comparison became rather unfair as the quantity and quality of light reaching the test plants under ~200 watt of cob was basically full shade. I did a reconfig moving the 5000k cxa3070 ~60w, to the main lettuce garden. Plan is to now fit a reflector to it, and make 1or 2 more to replace the 4ft T12 aquarium light. New sprouts, Butterhead, more romaine (planted deeper ~3/4 in vs. 1/4 in. to see if that helps with the floppyness), Alaska and Oregon peas, Collards, Turnip greens, kale, cauliflower, broccoli. Yet to sprout, coriander, carrots and onions.
Since putting the cob in here the Christmas cactus sprouted new leaves, the mother plant it was taken from is sprouting white/pink flowers under just window light.
In the far grouping of oregano the one closest to camera has about a 1 in. chute coming off it, this is the set that was part of original cob test, the one behind it the chute is slightly shorter and there is still a slight color diff.
"The Blurple Room"
A butterhead sprout culled from the herd and selected for a yet to be determined media swap (soil mix to 100% coco now) to some form of hydro or sips
That's it for now, Any suggestions on experiment ideas or nutes to use are appreciated, right now basically a light mix of cana veg.
Since putting the cob in here the Christmas cactus sprouted new leaves, the mother plant it was taken from is sprouting white/pink flowers under just window light.
In the far grouping of oregano the one closest to camera has about a 1 in. chute coming off it, this is the set that was part of original cob test, the one behind it the chute is slightly shorter and there is still a slight color diff.
"The Blurple Room"
A butterhead sprout culled from the herd and selected for a yet to be determined media swap (soil mix to 100% coco now) to some form of hydro or sips
That's it for now, Any suggestions on experiment ideas or nutes to use are appreciated, right now basically a light mix of cana veg.
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thetr33man
Well-Known Member
Ive had some inner leaf tip burn on my hydro lettuce under the Cidly Aquabars. Did a little research and its basically a problem of too much light and not enough airflow. Added a small fan to the area and also dialed back the light hours from 16 to 13. Hopefully that helps.
SSGrower
Well-Known Member
I have not seen any burn yet with 60W 5000k 16hrs., but just moved everything closer yesterday tho, how far from plants and what aquabar wattage?
thetr33man
Well-Known Member
From what I read, it can be caused by a combination of too much light and not enough transpiration or nutrient flow to the most rapidly growing areas, inner leaves. They get to the point where there isnt enough calcium to build cells and the tissue starts to die. Also some varieties are more likely to experience this problem than others, so its also somewhat genetic. Here is one article I read about it. http://www.e-gro.org/pdf/2015_431.pdf
VegasWinner
Well-Known Member
OneHitDone
Well-Known Member
robuncnn, I see that you are getting some of the deformation going on on your lettuce leafs. Do they have a thick "leathery" feel to them?
I have been playing around with some lettuce under HPS, Hortilux Blue MH, and a Cannabis tailored LED Panel (5K white, 630,660).
What I am noticing is massive root production under the led but stunted/mutated top growth that is very thick and leathery.
HPS seems to put on the most mass but the texture seems a bit off. The Horti Blue is beautiful all around.
I also noted a lot of that tip burn on the inner growth of the led that only shows up when the heads should be approaching finish time.
All lettuce is in coco and hand watered with the same hydroponic solution
My take away is that lettuce is very spectrum sensitive and I need to do more testing. I am hopeful to find an led solution that will work well in a stacked shelf system so I can crank out some lettuce indoors
Left to right - Hps, Hortilux Blue MH, LED
New grow issues on led
Variety #2 really showed different structures under the different light sources.
Left to right - Hps, Hortilux Blue MH, LED
I really appreciate you folks in this section of the site. Such great information being shared over here
robincnn
Well-Known Member
They do feel thick "leathery" on top. I also noticed that the roots developed very quickly under the LED and they were coming out of the hole under the pot. needs frequent water too.
Any idea how the spectrum looks like for Hortilux Blue MH
Saw a few research articles for 'Lettuce Spectrum' under google search and google scholar search.
https://www.researchgate.net/profil...ing_diodes/links/0046352fe59872cc43000000.pdf
https://www.heliospectra.com/sites/default/files/file_file/akron_whitepaper.pdf
Moved one of these to a 3500K tent to see if it does better.
thetr33man
Well-Known Member
One thing about lettuce is that TOO MUCH light is definitely a bad thing, commercial producers in greenhouses use shade cloth during the summer months to decrease the amount of light their plants get. Ive also noticed that under LED my colored varieties get VERY colorful, havent compared to outside yet, but plan to this summer.
Updated picture, since then I killed several of these plants by putting them in a bucket full of water for a few days, long story, kinda stupid. This was taken last weekend I think...
Updated picture, since then I killed several of these plants by putting them in a bucket full of water for a few days, long story, kinda stupid. This was taken last weekend I think...
thetr33man
Well-Known Member
I was thinking about popping 2 more holes in each lid, centered between each set of 4. I dont want to crowd the plants too much, but also dont like the idea of wasting a lot of light, which currently it seems to be doing. Those are 2" netcups for reference btw....
OneHitDone
Well-Known Member
I have not seen an independent spectroradiometer reading for the Hortilux Blue MH (kinda funny that the companies bragging about having that equipment and selling all these lamps won't post one)
This is the manufacturers advertised output:
I find that second reference in the first link you posted interesting. This is the question I need to have answered or answer myself with testing: Can white led directly replace white T5?
"However, during the last decade the progress in solid-state lighting, based on light-emitting diodes (LEDs) has facilitated the research on light quality responses in plants in general, and attracted much interest as a light source for assimilation lighting in greenhouses. On the other hand, artificial lighting with a too narrow spectrum is not spectrally optimal for normal plant growth (Brazaityte et al. 2006). In monochromatic R LED light, growth in several plant species, including lettuce, wheat, radish, spinach and pepper, was less vigorous than that of plants grown under white fluorescent lamps or metal halide lamps at an equal photosynthetic photon flux density (Bula et al. 1991, Hoenecke et al. 1992, Brown et al. 1995, Goins et al. 1997, Yorio et al. 2001). "