CFLs, Vegging and Watts Per Square Foot

Quazi

Member

• Sep 3, 2008

• #1

Hello fellow growers.



I'm trying to determine the finishing touches for my cabinet and had a couple questions about CFLs in veg:

1) Should you still use the 50w per sq ft formula as in flower?

2) If you use the above formula, do you use the actual wattage of the lamp or the incandescent equivalent? (I think I know the answer, but just want to be sure)

3) Daylight or cool white CFLs are the best for veg, correct?

Thanks ahead of time for your input!

 

knna

Member

• Sep 3, 2008

• #2

In late veg (already big plants) you can use same watts/sq ft than in flower, but most people uses lower irradiances during veg, about half in avarage.

But if you use lights with low efficiency (CFLs) then you need to use more watts to obtain same light. 30watt/sq ft of CFLs usually is a good rule of thumb.

2-Of course, true, actual watts. we never use incandescent equivalents for growing.

3-Correct. But any tone works if you dont find daylight (the best for veg).

 

Last edited: Sep 3, 2008

petemoss

Active member

• Sep 3, 2008

• #3

50 watts per sq ft is for HID lights. CFL lighting is different AFAIK. Most people aim for a certain number of Lumens per sq ft. DrBud uses over 7000 lumens per sq ft, I believe. His 42 watt CFLs produce 2800 lumens each.

 

Maj.PotHead

End Cannibis Prohibition Now Realize Legalize !!

Mentor

Veteran

• Sep 4, 2008

• #4

heres 420w in mixed color cfls unsure watt per sqft i have
each fixture has
45w=150w warm @2900 lumens 2700k
25w=100w daylight @1470 lumens 5,000k



heres a few plants in coco from same pic

 

Quazi

Member

• Sep 5, 2008

• #5

Thanks for the info everyone.

I think I'm on the right track now.

 

dirkdaddy

Member

• Sep 5, 2008

• #6

Maj.PotHead said:

heres 420w in mixed color cfls unsure watt per sqft i have
each fixture has
45w=150w warm @2900 lumens 2700k
25w=100w daylight @1470 lumens 5,000k



heres a few plants in coco from same pic

Click to expand...

kind of off topic but where did you get those "Y splitter" things you are using in your light sockets that allows you to plug two into one? can you get those at home depot/lowes?

 

Quazi

Member

• Sep 5, 2008

• #7

Funny thing, I had those things in my hands at Lowes about 20 minutes ago. They're 3 or 4 bucks. The splitter that is, not the plant.

I can't wait until the day that you can go pick up vegging marijuana plants in the hardware store.

 

Last edited: Sep 5, 2008