CFL Light Question

Help,
First time for me to grow. I went with CFL's because they are easy to get and don't produce a lot of heat. I have 2 four foot strips with daylight bulbs (4100k?) I read where people use these but no one says how many per plant. Do I need more bulbs and should I get some of the cool bulbs as well (3100K?) Maybe make half of bulbs the cool variety.. Would like to know how people are using these lights to grow.. Pictures would be nice...
Thanks

p.s. Can't wait for 1st. smoke!
 

HiIGrow

Member
Depends on how many plants you are growing. I use 3 26w 6500k daylight CFL's. This is enough to grow my 3 plants for a month. With your eight lights, you will be fine will putting atleast 6 plants depending on how long your fixture is. Also, make a reflector if you can, this will boost up the light!
 

massah

Well-Known Member
Ok...when it comes to CFL growing the more the better...to get ok yields out of growing with CFL's a good measure to use is 100 REAL watts of CFL power per plant. Keep em as close as you can without burning the leaves(usually 1-2" depending on how strong they are). You can also pickup the "300watt" equivalent bulbs at lowes for about $15 each, they are about 125watts of real CFL power, and you can leave a little more space between the plants and the light(about 4-6"). Just watch your temps and keep air moving, the more CFL's you add in a compact space the more heat will build up. With CFL's you want a reflector if you can get one, if you can't find any hell make your own from a soda can :)

In a nutshell: with CFL's, you want to get them as close as possible, and don't try to get too many plants under there or you'll just end up with small popcorn buds and not much for yield.
 
Thanks for the posts guys.. I am using 4' bulbs. I figure about 3 plants maybe 4 per 4'. I will add a 3rd. light as well and can make some reflectors when they get a little bigger, not sprouted yet, but anytime now.
 

Gastanker

Well-Known Member
I was pulling an oz a week with 388w of CFL here - https://www.rollitup.org/cfl-growing/165396-first-cfl-grow-help-appreciated.html

I would recommend a 3:1 of 6500K:2700K for veg and the opposite for flower.



Keep them small! CFLs don't do nearly as well with large plants unless you keep a clean scrog or LST. I started flowering at this size -



Dropping bulb between plants maximizes plant absorption without the loss of restrike like you would have with a reflector. I tried to cover the canopy in smaller bulbs and submerge larger bulbs between plants.



I would yield ~ 1oz per plant. With 6 in full flower at a time and two others just rotating into the flower box I was able to harvest a plant per week.



This took place in a 2x3x3.5' area of a small closet.
 
Excellent, nice picks... I am using 4' conpact strips, not sure they have 300 watt equivalent in them. Maybe I need to use individual bulbs, seem more versatile. I'm getting excited now.....
 
Well I went to Lowes and couldn;t find any 300 watt cfl bulbs there. I did notice that the 4' tubes I have are not the 6500k variety so i picked some up. Now 2 5000k & 2 6500K. Let's see what happens. Will look on the internet for the 300 watt cfl's. Tks
Lowes has these on the Internet:
http://www.lowes.com/pd_46931-75774-L65TN_0__?productId=3197521&Ntt=300+watt+compact+fluorescent&pl=1&currentURL=/pl__0__s?Ntt=300+watt+compact+fluorescent&facetInfo=

300-Watt Equivalent Indoor/Outdoor Compact Fluorescent Light Bulb

  • Twist light bulb
  • Uses 65 watts for 3900 lumens of brightness
  • Bulb life is 6000 hours
  • Medium base, most frequently used for lanterns and light sockets
  • Designed for outdoor use only
  • 2700-kelvin color temperature, Soft White light
  • Soft White light provides warmer ambiance
  • Light bulb dimensions 4"D x 9.5"L
What do you think? Maybe add them in woth the 4'tubes as well?
 

massah

Well-Known Member
wait...4' tubes...Unless you are getting T5's and have 4-8 of them, don't do it...regular old 40watt 4' tubes are not strong enough to do much with because of how distributed that 40watts is...you need the higher wattage T5's or T8 HO(High Output) bulbs and they are really only recommended for VEG, not flowering...some people do whole grows with them, but as far as efficiency's sake its better to go with higher wattage CFL's(compact fluorescent) bulbs instead as you can concentrate the light from them better on the plant where you need it.
 
Thanks, My bulbs are t8's after they get bigger I'll get some H.O. bulbs. Looks like I'll have to get the 300 watt ones from the Internet for about $25-$30 a shot. Don;t see any anywhere else. Tks
 

Gastanker

Well-Known Member
5500K is ok for veg. When people say 300w CFLs they generally mean 68w CFLs that have an equivalency to a 300w incandescent. Homedepot carries 68w bulbs (like the one's in my pictures), but not 300w CFLs.
 

frmrboi

Well-Known Member
. Looks like I'll have to get the 300 watt ones from the Internet for about $25-$30 a shot. Don;t see any anywhere else. Tks
if you're buying online anyways don't waste your money on cfls, unlike Gastanker I feel your just throwing away 3/4 of your light energy without reflectors.
For what all the hardware needed to build that contraption would cost you could buy a 400 HPS light WITH reflector and ballast. You'd get triple the harvest with that. http://www.htgsupply.com/Category-400-Watt-Magnetic-Grow-Light-Systems.asp

5500K is ok for veg..
but that's not what he has, there's a huge difference between the two as far as plant growth goes.,,

 

waffles696

Active Member
the stems on a few of those saplings are lanky, you might want to cover up the stems a little so they dont topple over and you end up with a broken stem and a dead plant.... they are lanky because the light is far away from the sapling and they are trying to get closer, might want to have a light closer to the sapling
 
I dont want to have to wear suntan lotion and sunglasses when I go in the grow room and then there's the problem of removing all that heat with expensive fans... Ill stick with the cfl's. Thanks
 
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