Growing hot peppers/tomatoes with Citizen COB - color temp

The H1R0

Active Member
Hi guys,

I'm new here and growing peppers and tomatoes indoors in winter before they go outside in mid-May as soon as temperatures allow them to stay outside. I'd like to ask you a few questions as I'm an LED-noob and this forum clearly has the most knowledge about growing with LED of any community. Way to go, guys.

I'm planning on using CLU048 1212 for a DIY COB setup. First question I have: What color temp is best for growing those plants? I've been reading contradicting info, so I'm confused now. As of now, I'm thinking 4000k would be nice. CRI 80 or 90? Or 3500k? Or 5500k? I don't plan on fruiting them indoors, but might use the setup to grow some herbs/lettuce indoors as soon as the peppers go outside. I want compact, nice growing plants that are healthy and ready for the outdoor pot life as soon as they go outside on my balcony.

As of photons: Am I correct that around 500ppfd would be sufficient, or should I go further? Or is that too much for peppers and tomatoes? Growing area will be 1.2m * 0.8m, so that's roughly 4ft by 2.5ft.

Also: Anything I'm missing for now in my consideration? Selecting parts and stuff will be the next step.

Thanks for your help!!
 

frica

Well-Known Member
Pepper and tomato will fruit the moment they get the chance, the only way to stop them from fruiting is using fertilizer specifically high in N.
Generally it's not something desireable once you want fruit, but since you're vegging, a lot of N means the plants put all their energy in foliage growth and just drop their flowers.

Colour temp doesn't matter too much, though a high colour temperature is generally preferable for vegetative growth.
4000K is a nice can do it all well colour temp, but you may want to go with a higher colour temp.

500 ppfd is sufficient.


Also put a fan in the room to blow wind on the plants, tomatoes and peppers can produce very weak stems if there's no wind.


And like always, plants have to be eased into outside life a little once they go outside.
Going from growroom conditions to direct full sun causes a bit of stress.
 

The H1R0

Active Member
Thanks for your reply! Fertilizer is all set, I have that already. Regarding color temp - is there a formula like: The higher the color temp, the less stretch during vegging? The lower the color temp, the more the plants stretch? Is it that simple? Also, CRI90 COBs have lower lumen output, but have better output in PAR region, am I correct and thus are not as much less efficient as looking at the pure lumens/watt would suggest, right? Which is to be preferred?
 

frica

Well-Known Member
Thanks for your reply! Fertilizer is all set, I have that already. Regarding color temp - is there a formula like: The higher the color temp, the less stretch during vegging? The lower the color temp, the more the plants stretch? Is it that simple? Also, CRI90 COBs have lower lumen output, but have better output in PAR region, am I correct and thus are not as much less efficient as looking at the pure lumens/watt would suggest, right? Which is to be preferred?
Light intensity has more to do with stretching than the colour temp.
You could veg under a 2200K HPS but never experience any stretch because of the light intensity.

You're correct about the 90CRI COBs, currently people really like the high CRI COBs.
But both kinds work.
 

The H1R0

Active Member
Okay, great. So for my purpose of peppers and tomatoes as well as salads and all that stuff, I'd most likely be happy with 4000k 90CRI, I suppose.
 

thetr33man

Well-Known Member
Id go with 3500k 90cri if I were you. Little better red shift might help in case you ever wanna grow 'something else'...
 

The H1R0

Active Member
Thanks guys! Read more and am confused again. Can someone explain to me, why I should use 90CRI instead of 80CRI? The 80s have about 20% more lumens output.
 

frica

Well-Known Member
Thanks guys! Read more and am confused again. Can someone explain to me, why I should use 90CRI instead of 80CRI? The 80s have about 20% more lumens output.
Lumens are for our eyes, which are most sensitive to green (555nm), and less to wavelength farther from green.
90CRI white has more light in the far red range, so our eyes are less sensitive to it.


Plants have a different curve for photosynthesis.


But both 80 and 90 cri will grow very well.
The difference in efficiency for photosynthesis is rather small.
 

OneHitDone

Well-Known Member
A lot has to do with structure and quality of plant material you are looking to produce. Especially since your clearly intending to move them outside.
The "Transcend" Led Tubes/fixtures appear to be on the right track but I have not yet had a chance to see them first hand.
Maybe a combo of some led tubes with a few Hortilux PowerVeg T5's mixed in to pretty much "pre-harden" them for outdoor life?
Hopefully you post back with what lights you end up growing with and of course the results.

Also, you may find some info in my other thread on growing lettuce indoors
https://www.rollitup.org/t/all-cob-users-lettuce-grow-challenge.905662/
 

The H1R0

Active Member
Excellent! Starts to add up now. I've only been looking into LEDs for a few days and am learning a lot in this community. Thank you! My setup will be open with no walls, right next to a west-facing window - the LED system is supposed to help establishing a correct daily lighting routine as daylight currently is not sufficient for my peppers.

Budget is not endless, as for now I'm thinking about 4 or 5 CLU048 1212 with ModuLed 13450-HBG and Meanwell HBG-60-1400 setup as luminaries so I have maximum flexibility in moving the lights around if I split up my growing place or whatever comes to my newbie-mind. I want to run them at 1400mA for the peppers, so that's about 50W. I will be hanging them from 7€ IKEA clothes stands, it'll be interesting for sure. Does this combination of heatsink, COB and driver work?

Gotta read the lettuce thread now!
 

thetr33man

Well-Known Member


Almost same thing, moduled 9980 sink, 1.4a driver, clu048-1212 @ 4000k cob. Heatsink gets a little warm, good idea going with next size larger...
 

The H1R0

Active Member
Looks great! I actually would love to use the 134100, it should cool the COBs really nice, but I can't get ahold of them anywhere in Europe with reasonable shipping costs, it's really frustrating.
 

The Dawg

Well-Known Member
Top