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Discussion in 'Growing Marijuana Indoors' started by Silhouette, Jan 22, 2009.

  1. Blue, red?!? o_0 If I went and used CFL's to grow a plant, could I use full spectrum bulbs throughout the whole growing process? Or should I buy each spectrum bulb differently? (I'm new to this, ahah)

    Please, explain.
  2. #2 abnormldood, Jan 22, 2009
    Last edited by a moderator: Jan 22, 2009
    I wouldn't get the full spectrum bulbs, they wouldn't get you full results in either stages of growth. You are going to need as much effective lighting as possible with CFLs. Get the blue spectrum(3500 kelvin) bulbs for veg, then switch over to the red spectrum(6500 kelvin) for flowering. Be sure to place them within 2 inches of the plant.
  3. Okay, thanks.
  4. #4 bennyweed, Jan 22, 2009
    Last edited by a moderator: Jan 22, 2009
    Not to be an ass but the previous person has the spectrum's mixed up..just Google it man. 6500k is a blue spectrum that's what plants require for proper vegetation growth. That's why metal halides are around....for the flowering stage you want the lower end of the Kelvin scale which I would suggest 3500k and below....anyone else chime in here if I'm wrong

    ---kelvin is just another from of temperature that light spectrum's are based upon.
  5. benny is right, 6500k(blue) for veg, and lower end of the scale (red) for flowering...3500k would be fine, i use 2700k

    to achieve the full spectrum of light through the whole grow, use a mix of these two. start with more blue bulbs than red, and start adding red bulbs to the grow as you get closer to flower.

    this also works because you wont use your full arsenal of lights on seedlings who cant use it all, so your not wasting electricity

    like, start 4 blue bulbs 2 red bulbs. or 2 and 1 if youre doing a real small grow.
    after a couple weeks, add a red or two

    by the time your flowering, youre doing like 2-4 blue bulbs, and 4-6 red, giving you the full spectrum
  6. #6 OldSkool1010, Jan 22, 2009
    Last edited by a moderator: Jan 22, 2009
    Color temperature
    "Warm white" or "Soft white" < 2700 K
    "White", "Bright White", or "Medium White" 2900 - 3000 K
    "Cool white" 4000 K
    "Daylight" > 5000 K

    Color temperature is a quantitative measure. The higher the number in kelvin, the “cooler”, i.e., bluer, the shade. Color names associated with a particular color temperature are not standardized for modern CFLs and other triphosphor lamps like they were for the older style halophosphate fluorescent lamps. Variations and inconsistencies exist among manufacturers. For example, Sylvania's Daylight CFLs have a color temperature of 3500 K, while most other lamps with a "daylight" label have color temperatures of at least 5000 K. Some vendors do not include the kelvin value on the package, but this is beginning to change now that the Energy Star Criteria for CFLs is expected to require such labeling in its 4.0 revision.

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