Need CFL help for my first grow

K

Klaas

Active Member

• May 19, 2012

• #1

Hey yall, I have a few questions about CFL's before I get started on my grow...

Do lumens matter or does color temperature what I'm shootin for?

I know 2700k color temp is what I want for flowering, and 6500k for vegging
but can I use 5500k for vegging instead? I'm having trouble finding many 6500k CFL's.

Thanks, I appreciate whatever input anyone has.

 

K

Klaas

Active Member

• May 19, 2012

• #2

also, I just noticed CFL's have a CRI rating. Is high better?

 

K

Klaas

Active Member

• May 19, 2012

• #3

another question, should i use less CFL's while its still sprouting?

 

Psychonaughtical

Active Member

• May 19, 2012

• #4

5500k is apparently ideal for light absorption so go wild,

Here is my reference, Right hurrr

 

Psychonaughtical

Active Member

• May 19, 2012

• #5

Cfl's while sprouting are fine and are what most people use before switching to higher powers, just don't keep them too close. A lot of their growth comes from the energy stored inside of the seed so keep them around for when they need it.

 

scroglodyte

Well-Known Member

• May 19, 2012

• #6

less while sprouting, more while vegging, even more in flower.
lumens relate to human vision. watts and color. lotsa watts...........blue then red.

 

ExIzTenChal34

Active Member

• May 19, 2012

• #7

6500 K is the perfered spectrum for vegging & as for 2700 is for blooming but both would work fine during any stage tbh it's not something that needs to be followed as tedious as they make it sound. I perfer full spectrum all the way ya know why not work with both & experiment see what you like man. Good Luck!

 

scroglodyte

Well-Known Member

• May 19, 2012

• #8

i like to mix it up too. more blue than red in veg, and then opposite

 

K

Klaas

Active Member

• May 19, 2012

• #9

thanks guy for all the input so far

keep postin away !

i need t3h infoz

 

Davidsnow

Active Member

• May 19, 2012

• #10

for CFL's I find 100-150 watts per plant is a safe bet, usually. For seedling stage, honestly 2 weeks at a bright windowsill works well, but if you start out with sunshine only, they may get shocked with the heat, and moreso the intensity of ~5-12 CFL's! What you CAN do is once it germinates, put it next to a windowsill or under 1 CFL until it comes out, then slowly add lights up to 100-150 watts of CFL. Then when you switch to flowering keep the same # of lights and swap the 6500k for 2700k and vice versa

veg = 3:1 ratio of 6500:2700 lights (3 6500's, 1 2700)
flowering = 3:1 ratio of 2700:6500 lights


hope I helped!

 

K

Klaas

Active Member

• May 19, 2012

• #11

thanks m8 i know a lot of these things but it always helps to get input.

Does anyone know much about Color Rendering Index (CRI)? i would like to know the importance of this if any.

 

Davidsnow

Active Member

• May 19, 2012

• #12

EDIT: The higher CRI won't have much of an impact. Higher CRI usually means that it looks brighter to the human eye, not to plants. There is some speculation that a higher CRI = higher output of lumens, but it shouldn't correlate.