Understanding Lighting Spectrum

[zq8s10]

Okay, well I just now read and found out somewhat on the lighting spectrums , but the other night I went to walmart and bought some 42w 2700 lumne cfls, 2 of them, but I dont think that they are blue spectrum, I believe they were in a yellow looking package and they are GE (General Electric) but I think that the pack said soft white or something , I was setting up my closet and I was going to have 2 of these on each plant, with 2 48 inch floros hanging over them, so every two flower pots is going to have 4 cfls with 2 48" flouros hanging over them, So does it really matter that they are soft white? can I just the the 48" tubes in a blue spectrum? and then when I go into flowering just switch them out to a red spectrum tube? and just keep the cfls I got from wal mart for the whole grow, Thanks for all the help I can get in advance, I'm about 45 bux away from finishing up my grow closet , and I dont want any set backs, however, If I have to wait , I can replace the bulbs, just will put me back another week till I can start growing. Thanks

[Dipper14]

Your looking for the kelvin rating. You said they were soft white, usually around 3500k, for flowering you want 2700k which is warm white, you might want a higher kelvin rating 4000kish (coolwhite) for veg.

but the softwhite will work just fine if you want to use them.

[McTwist]

Don't worry about it man. I have six 23 watt 2700k and two 40 watt 3000k bulbs. They will work fine. Growth won't be as nice as someone with an MH or a 6500k CFL but it'll work fine. Growth will be a tad sketchy during veg but it'll bounce back in flowering.

[zq8s10]

Alright good, I will buy the blue spectrum floros to hang over the plants tho, this should help a little being their the ones hanging 2 inchs off the plant, how far away from the sides of the plants should I put the cfls? .. I'm still curious to how bad it will mess with the growing, I worry about every little thing, does walmart even sell blue spectrum cfls? if so I think I still got the receipt and ill just take the two that I bought back and get blue spectrums if they got em , thanks for yalls replys, I love the city, and thanks in advance for further help

[zq8s10]

Anyone?!

[urgr8estfear]

Most people talk about 2700k red spectrum and 6500k blue spectrum CFLs.
It's really more like red-ish and blue-ish.
2700K CFLs produce some blue light too and 6500K CFLs produce some red light.

This is what I use :

4000K coolwhite'wide spectrum' fluro tube :



and then 'for the reds' 2700K CFLs:



Its all about efficiency.

The 'wide spectrum' flurotube I use does 1200 lumen/18W
The narrow CFLs i use also does 1200 lumen/18W
BUT, a flurotube with a similar spectrum as my CFL does 1500 lumen/18W.
This is because tubes are more efficient per W then CFLs.

This whole spectrum thingy has everything to do with photosynthesis.
Photosynthesis requires chlorophyl which use these spectra :



Do you get the picture now?

[Mr. Muffin]

this is the easyest spectrum graph ive found so far, just try to match ur lights with the higher parts of the graph