How much light is "too much"!

[dakotamoon]

Just about everything I read tells me: "you need more light" .. so with all the "reasonably" priced cfl and led options: how much light is too much?

I have a 6 COB light which claims to be 1800 watts, I also have 4 sylvania/feit led cob lights on a strip, and a cfl strip for flowering.

With canopy coverage being the hot point, why not just keep adding 5000 kelvin cfl's .. to surround the plants....has anyone developed a way to "surround" plants with light? When does this lumens search become pointless?

Just wondering!

 

[Butter Milk]

Honestly, an awesome question. Very interested in the answers. I am growing 2 autos with 4 - 65w equivalent LED’s and I think it’s plenty of light. I’m sure if I was using a square 1000w equivalent instead, would that be too much, I only have 18”x18”x4’ of space. Maybe 1500w!?!?!

 

[dakotamoon]

Thanks Mr. Butter.. towards the end of my first grow, I was throwing more lights at my plants, with low wattage CFL's and LED grow lights being an option .. when do you say .. Too much?

I have 1500W COB array x 6, 2 par 30 - 2 pAR 38 Growlight bulbs .. Sylvania and Freit .. 18 Watts each.

1 2 foot cfl lighting strip.

I have a whole bunch of daylight cfl's .. and plan a "sleave" of light for blooming plants, but when is the .. No Mas Light moment?

 

[Ganjagrowergu]

Until I switched to QBs I shot for 50 watts actual per square foot. With 240w of quantum boards and an old blurple LED I hit just under 40w/sq ft in 10.6 square feet

I was doing fine at 24w/sq ft before I added the old blurple, just needed something to even up the footprint.

Using watts per square foot is not the best way to measure but it gets you there

 

[Organic Rich]

this post gave me a great idea to "surround" my plants with a light boost at the flowering stage. A 2000 watt LED will be the only light for the vegetative stage and then the boost lights come on for flowering in a 5 X5 grow. These lights would be 2 - 200 watt LED's with a single strip 50watt LED in the back, thank you!

 

[MassMedMan]

When the electric bill gets to high...... or the plants tell you. Or, it becomes dangerous.

More doesn't always equal better, or quality.

I've used reptile lights late in flower to help with uv. Hung cfls & t5 bars on the side of my walls for extra side/lower penetration.

And, what I got was hard to measure, and quick to become dangerous.

Never overload your circuits. or power strips. Or use crazy extension set ups.

I bought good lights and that worked for me. Test results proved that. Everyone is going to be a little different. Those are my thoughts.

Good luck, have fun, and be safe. No need to burn it down until you want to.

 

[PurpleGunRack]

Basically going above 1200 PPFD doesn't do much unless you have a fully CO2 controlled environment.

PPFD Graphs and Analysis

why not just keep adding 5000 kelvin cfl's

Because they're inefficient and have to be very close to the plant

I have a 6 COB light which claims to be 1800 watts

That wee lamp should be 1800w..... more like 300w total, not 300w per COB...

 

[Mars Hydro]

Check their real wattage, not the advertised one. For led growing, you will need 35~50w/sft. As long as the total wattage is not above 50w/sft, your plants should be okay.

 

[LEDXpert]

I'm going to tell you with a bulb like that you will never have to worry about too much light only too much heat.

There are LED manufacturers out there selling 2000w (real wall draw) LED lights at high efficiency for that matter. At some point the plant gets saturated with light and the added light has a diminishing out put. This is in the umol/m2/s of over 1000 the output curve starts to slow down. People do this many because they are space limited and the energy costs are worth it to them. This is to maximize g/sqft. If you're maximizing g/w then you'd for sure not go over 1000W of overhead and probably a bit less like the 600W range and divert that energy to more grow space for better weight results.

 

[dakotamoon]

It seems to me from the online and hydro store research that I have done: The "wattage" listed on the led lights is pointless at worst and disingenuous at best!

My aim was to surround my plants in the flower stage with as much light as I could provide to them! So far I have:

One "1800 watt" Cob led! Then when my plants went to bloom I added: 1 6400 kelvin cfl which claims to be 39 watts!

Then I added another array of par 30 and par 38 led grow bulbs from Sylvania and Feit .. they claim to be 9 watts each, the fixture I found lets me add 4 of these bulbs to another array.

Then I added cfl fill bulbs (x4 - 5000kelvin on a moveable stick) - thinking that the buds - just needed love and light.

Unfortunately my first grow developed "root rot", but boy were the buds ever illuminated.

All We can do is to try and provide the best environment possible, and cross our fingers.

 

[Organic Rich]

Check their real wattage, not the advertised one. For led growing, you will need 35~50w/sft. As long as the total wattage is not above 50w/sft, your plants should be okay.

Thanks to you and a couple of others on other MJ forums I have come down to earth on the size of my grow and gotten myself an education on grow lights. Finally settled on just three plants, one each in 7 gal fabric pots with a 285 watt HGL 2 quantum boards. In addition I will have small wattage (40) watt LED strips on 3 sides plus the Growstar LED 2000 (actual watts 400) hanging alongside the HGL boards over the plants (raised as needed from 18" to 24") Everybody has an opinion about what works but only an actual grow will tell the tale!

 

[dakotamoon]

Wow, I can relate to your learning curve.. I have learned more than I ever "wanted" to know about growing marijuana!

But the learning curve goes on forever, I'm okay with that... it keeps me young.

Nice concept with the fill in lights, that's what I was looking for on a much smaller budget.

Keep us posted on how these fill lights affect your harvest, thanks.

 

[GrizzWald]

More light, means more environmental changes to you area. But I can't see where you would have too much light, wouldnt be able to fit it in your area... Your not going to compete with suns output nor the breeze from a tree or atmospheric pressure...

 

[dakotamoon]

I posted this thread, because like all of You .. during veg I was more than happy with my lighting, but in the bloom stage - I could see so many trichomes near the bottom the plant not getting light. As stated above this is my first grow, I didn't want to practice any grooming - in my first grow. But now that I have my tent legs, I can see how plant training can mitigate the lighting panic during bloom stage.