All COB Users - Lettuce Grow Challenge!!

I would like to challenge any and all here on RIU that are growing with cobs to grow a few heads of lettuce under their lights.
Come on guys and gals, I know you have some extra rockwool cubes, rapid rooters, germination mix and all that laying around. Grab yourself a pack of bib or romaine lettuce on your way out of Wally World and sprout a few up so the rest of the growing word can see how well / if cobs are up to task for food production.
Let's just see if cob can do it start to finish

For the investment of cobs I'll use them for their intended purpose

Streetlights or warehouse lighting?

yeah its like april

sun is out

I can see we have a few really inspirational curious types on board already

I think there is a lot to be learned about all lighting techs from growing multiple species. It seems as though this group is the hotbed for the diy cob movement so it would be a great place to also have it demonstrated that it is a usable tech for plants across the board.

Maybe we can get @AquariusPanta in here to grow some. No need to be all sketch on legal issues or anything growing some Dank salad

OneHitDone said:

I can see we have a few really inspirational curious types on board already

I think there is a lot to be learned about all lighting techs from growing multiple species. It seems as though this group is the hotbed for the diy cob movement so it would be a great place to also have it demonstrated that it is a usable tech for plants across the board.

Maybe we can get @AquariusPanta in here to grow some. No need to be all sketch on legal issues or anything growing some Dank salad

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Oh, look- our first volunteer!

Pics or it didn't happen!

we are growing aquaponic salad greens..we have tried china panels, custom made china led bars..they all work

have some cobs..at this point waiting for arrival..so selfishly not gonna donate them to the test..
i have been generous enough to the project[lol]

i will add i AM interested in how cobs will work..and the amount of coverage..

winner ^^^^^^^

Wooo Hoooo, you mean I can actually do something more globally beneficial instead of just sitting in a small insular world????

What's in the pics
A 3 year old pansy that sprouted in August and got a foot of snow on it in september, I've taken about 8-10 clones off it
A potato in the bucket
Strawberries - Read somewhere the blurple color of a discount led I have is good for these - Comments?
Jalapeno and Bell peppers
A tray with more salad mixins
and an Avocado pit that has no chance in hell of sprouting.


As you can see I have been neglectful but now give me some motivation to do it right!!!!Under a fluorescent light for now but have 2 CXB 3070 at 3500k slated for this project driven at 1.2amp serial or parallel (depends on how thermal cooling an power generation experiment tie in)

2x Vero 29 5000K 70CRI 1.5Amps
Basil, Lavender, pepper, lemon thyme, strawberry, Tomato, miniature orange, marigold

robincnn said:

2x Vero 29 5000K 70CRI 1.5Amps
Basil, Lavender, pepper, lemon thyme, strawberry, Tomato, miniature orange, marigold
View attachment 3654013

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That looks really nice! You mean, COBs can grow something BESIDES weed? Who knew?

I built some cob veg panels for my snapdragons and will have no use for them for about 8 months after my flower/vegetable garden goes in, in about a month. I'll volunteer to slam out a couple of heads of lettuce under my lights.

OneHitDone said:

I can see we have a few really inspirational curious types on board already

I think there is a lot to be learned about all lighting techs from growing multiple species. It seems as though this group is the hotbed for the diy cob movement so it would be a great place to also have it demonstrated that it is a usable tech for plants across the board.

Click to expand...

So I must have been working on this while you were conjuring up this little idea and I'm not sure who should be more frightened, me or you. Strong work in the cup challenge there One (others too but damm dude) - rootbound plant because you can - Why? - see previous answer.

Transplanted 4/8 and 4/9 Bell Pepper from a grocery store (maybe organic, I had to try a couple) that sprouted 2nd and 3rd week of March.
This one -


is under these:

8 lamp 2ft T5 (2900,6500), I cant remember shit so based off memory which will be close here goes CXA3070 arrays 2-5000, 1-4000, 1-3500, 1-3000, 1-2700 driven at 3 x 42v 1.5amp 2 COBs in parallel on each, a rebuilt 2 COB light with CXB 3070 3500 @ 36v 1.2amp parallel, and a partridge in a pear tree.

These -

Are under 4 T5 (6500) 2ft and 2 13w home depot red, blue, white "monochromatic" led screw-in bulbs.

And the others are in my crappy pic in my first post 2 lamp 4ft aquarium and window light, to have 2 cxb3070 (3000).

OLD MOTHER SATIVA said:

View attachment 3653966 we are growing aquaponic salad greens..we have tried china panels, custom made china led bars..they all work

have some cobs..at this point waiting for arrival..so selfishly not gonna donate them to the test..
i have been generous enough to the project[lol]

i will add i AM interested in how cobs will work..and the amount of coverage..

Click to expand...

Can you tell me what make/model those led bars are?

I'll be growing some lettuce under CXB's in a few weeks. For now a picture of my first few cob units. No lettuce, nothing fancy, just some gen 1 vero 18's @1.4 amps. Please try to ignore the fire hazzard wiring =/

OneHitDone said:

Can you tell me what make/model those led bars are?

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we had them custom made "younowwhere"

we got three different styles cree, bridfleux and yeh epi..in mixtures of red blue and white

we also bought some cheap panels

my other input is that possibly salad greens do not need the extra oomph that cannabis does and

a. we may get away with just using red and blue..one may look for the best $ per w

b.the other thing is that i am not willing to donate any of the cobs i am getting for salad greens [yet]no matter how noble it is..

i sefishly wanna try on herbage

OLD MOTHER SATIVA said:

View attachment 3653966 we are growing aquaponic salad greens..we have tried china panels, custom made china led bars..they all work

have some cobs..at this point waiting for arrival..so selfishly not gonna donate them to the test..
i have been generous enough to the project[lol]

i will add i AM interested in how cobs will work..and the amount of coverage..

Click to expand...

woooooooooooooooooooooooooooooow. Those are some very nice looking greens. Damns.

Quick status update, after 3 days of cob lighting growth of the strawberries, pepper and oregano seems average or on pace with flou/window light, chives seem robust. note all seem to have almost imperceptible color dif, posibly due to cob intensity, it didn't show up well in any pics.

Red lettuce, romaine seedlings, spinach, carrots, beans, broccoli under a Tasty T4-1750 on "veg", naturally.

topcat said:

Red lettuce, romaine seedlings, spinach, carrots, beans, broccoli under a Tasty T4-1750 on "veg", naturally.

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Where those just moved in or germinated there?