CFL'S Whats best for veg/flower? Watts, Lumens?

[LetsSeeYa]

Ok i have read a lot of grows here with cfl's and no one really has a standered of light as to how much to veg/flower for optimum growth. With all the cfl growers now, wouldn't it be nice to find some sort of standard guideline. As of now, its just the more the better it seems, or someone that thinks they can use 1 cfl from start to finsh. Im not saying some people have it dialed in, i could put out some names, but we all know who you are:thumbsup:

I wondered if we could do some side by grows to try to find, best over all lighting and possibly find a standered which a cfl grower can count on?

Now yeah im new and this might be a dumb question, but iv read many threads that really dont get into what, when and how. My reading is 5k to veg and 27 to flower. But iv read so many threads where this is not the method with cfl's, yet fantastic grows are coming from these cfl's:thumbsup:

So, i anyone is interested in a cfl ''how to grow'', jump in, or if im asking a really dumb question and have these answers, post em. Now this could be an easy question to answer, 5k to veg an 27 to flower, but thats not what im looking for. Only because people that use cfl's, i think try to keep to the ''rules'', but simply dont, yet great grow's. This would help me and many other people that are starting off growing indoors that just cant swing the killer light system's that are out there. Yet.

Any information or input is welcome and appreciated:thumbsup:



:rasta:

LetsSeeYa Reviewed by LetsSeeYa on 12-03-2009. CFL'S Whats best for veg/flower? Watts, Lumens? Ok i have read a lot of grows here with cfl's and no one really has a standered of light as to how much to veg/flower for optimum growth. With all the cfl growers now, wouldn't it be nice to find some sort of standard guideline. As of now, its just the more the better it seems, or someone that thinks they can use 1 cfl from start to finsh. Im not saying some people have it dialed in, i could put out some names, but we all know who you are:thumbsup: I wondered if we could do some side by Rating: 5

[achilles]

lets aim for sticky status!

1. cfls light penetration is not on par with HIDs, so distance from lights should be kept to a minimum (around 2"). This also means the lower branches will not get as much light, requiring additional side lighting.

2. cfls come in cool white (vegging, blue tint, 5,000k), and warm (flowering, red tint, 2,500)

3. CFLs are not cheaper per lumen as HIDs, but for a small grow can still be very economical.

4. Look at lumens, its suggested to have a minimum of 3,000 lumens per square foot of grow space. with a standard 100watt equivalent cfl bulb making 1,700 lumens, 2 per square foot is about right.

[LetsSeeYa]

lets aim for sticky status!

1. cfls light penetration is not on par with HIDs, so distance from lights should be kept to a minimum (around 2"). This also means the lower branches will not get as much light, requiring additional side lighting.

2. cfls come in cool white (vegging, blue tint, 5,000k), and warm (flowering, red tint, 2,500)

3. CFLs are not cheaper per lumen as HIDs, but for a small grow can still be very economical.

4. Look at lumens, its suggested to have a minimum of 3,000 lumens per square foot of grow space. with a standard 100watt equivalent cfl bulb making 1,700 lumens, 2 per square foot is about right.

Well i thought it would make a great sticky, but thought id wait to see what kind of info we get. If we continue to get the stuff like you just providid, its gotta be a sticky.

Its interesting because my 26wer's say that they are 1,750? Plus the 30w i just got said 2,100 lumen's. Also, many are not marked as cool, or warm. Not a one of mine were.

Well lets hope this thread takes off:rasta:

[Hempsouth]

From what I am learing with CFL's you cannot get too much light in a small space, meaning if its crowded with 4 bulbs say in 18" sq. then its probably good for finishing a main cola. The CFL's suck at penetrating below the upper fan leaves. Currently I am experimenting with them vertical on 1 side of the plant. You have to get them really close and have good reflective surroundings.

Just like with any grow light you must keep the ambient temperature down around the plants, it will always be warm above the lights.

[GreenGopher]

lets aim for sticky status!
2. cfls come in cool white (vegging, blue tint, 5,000k), and warm (flowering, red tint, 2,500)

4. Look at lumens, its suggested to have a minimum of 3,000 lumens per square foot of grow space. with a standard 100watt equivalent cfl bulb making 1,700 lumens, 2 per square foot is about right.

Referring to #2, thank you for this info. I've been searching for an answer like that for a while and i finally stumbled across this thread and I'm very happy that I did. Thanks to Achilles and Letseeya for the info from this thread.

Referring to #4, I have the same question that letseeya posted. It's strange that I hear about 100w CFL's that produce 2k lumens, then I read a grow log and someone says that they have a 30w CFL that produces 2.5k lumens (not factual, just an example). How is that possible?

Another question...how do lumens work excactly? I read somewhere that you don't just add them up. What matters most is the same type of lumens or something like that? I read this on a grow log, but the description was far too confusing for me to follow. A simplified answer for a noobie would be much appreciated!

[redtails]

Different makers have different lumen ratings, and also I noticed some say 100w or 150w equivalent but are different actual wattages(23-26w, 40 & 42w). I have one cfl growing 4 plants in a 4sq foot box right now, 3 budding autoflowers and a kushberry potential mom under 24/0 with a 200w(600w equivalent) 2700K cfl that puts out 12,000 lumens. I keep the tops within 2" of the light because it really doesn't penetrate more than maybe 8" too effectively.

[Roughrider]

You should have a look at the

http://boards.cannabis.com/indoor-li...uch-light.html

thread, which is stickied and answers many/most of these questions.

Lumens are a measure of the power of light as perceived by the human eye. (And before anyone starts to talk about plants "seeing" differently...the human eye is able to perceive light in the wavelengths used to grow.) You can grow a plant with 3000 lumens per square foot, but you're definitely on the low end with that. 5000 lumens per square foot and up is what you want to strive for.

As noted, CFLs don't have much canopy penetration. Distance form the plant is much more important for CFLs. Light from any source decreases in intensity in exponential relation to distance; the amount is the square of the distance form the source. Double any distance from a source and the amount of light will be one quarter of the previous amount. If you've got an HPS light, the 1 1/2" difference between 7" and 8 1/2" won't be huge. With a CFL, the difference of 1 1/2"...going from 1 1/1" from the plant to 3" from the plant...is the difference between getting some buds and getting nothing.

For vegging, you want to find what will be called "daylight" or "full spectrum" bulbs. They should be 5500k to 6500k.

For flowering, you will want to use "warm white" bulbs. These are more common. They are usually 2700k.

Ignore the "watt equivalent." Watts have nothing to do with growing. Watts are a measurement of energy, not light. Lumens aren't perfect, but they're more than accurate enough to determine if you have enough light.

[jtsik330]

Here is a little CFL contraption that i made that did wonders inside of my rubbermaid grow. However it did take time to make sure the lights are slightly adjusted acouple times a day. I would say that this would work awesome for anyone that can LST there babies. It just makes it easier since all of the light was focused from the top.

12 26 watt cfl's (1600 lumens each) in a space of 18'' x 16"


I drilled holes into the wood because i figured the hear would rise through those holes. Plus i had a 80 cfm in the center section blowing heat out of the box. Hope this helps someone!!

[Charbud]

Cfls do suck when it comes to penetration. I bought a huge one thinking it would work but still only the main cola really grew that well. I would reccomend lst technique because it would make your coverage of light more even !

[Faddenator]

My suggestion is to surround your plant with as many cfls as possible: 6500K for veg, 2700K. (bulbs should give color temp. on the packaging, if not, you probably dont want it ha). surrounding your plants as tight as possible will help penetration. The result is a slightly smaller top cola, but a bushier middle section. this means bigger yield.

Take a look at my setup, I posted a pic. I have about 12,000-13,000 lumens in this space (4x27watt 2700k cfls, 1x42 watt 2700k cfl, 2x32watt 6500K tube flouro.) there are three cfl's surrounding the plants, one (the 42w) above all three, and one extra on top of the heavily budding one (not visible). I will move this extra one around as they finish. I saw a significant increase in the lower half of my plants once the lights were moved from all on top to this.

Hope this helps. :thumbsup: