i wanted to use 3 of these cfl's TCP 68 Watt (300W) SpringLight Soft White 1 Pack - at The Home Depot and put reflectors on them, and then have some lower watt cfl's hanging down in between my plants like these ones Amazon: GE 13-Watt Energy SmartTM - 8 Pack - 60 watt ouput because i have heard that with the spiral bulbs most of the lights go out to the side, do you think that these bulbs would be efficient for 4-5 plants ?
Will i have enough cfl's?
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Re: Will i have enough cfl's ?
If you will tell me the grow space area size, I will calculate it for you. Or I can give you a link to read up on HOW MUCH LIGHT IS NEEDED and the formula to calculate it.
Those 13 watt bulbs are not that desirable and not that much cheaper than the 42 watters.
Pleae consider reading the first page or two here: CFL Light Tutorial
If you will tell me the grow space area size, I will calculate it for you. Or I can give you a link to read up on HOW MUCH LIGHT IS NEEDED and the formula to calculate it.
Those 13 watt bulbs are not that desirable and not that much cheaper than the 42 watters.
Pleae consider reading the first page or two here: CFL Light Tutorial
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Re: Will i have enough cfl's ?
my grow space is about 4' by 3', and thanks for the link i didn't see it
Re: Will i have enough cfl's ?
How much light is needed for growing?
Depends on the size of plant you are trying to grow. I'll try to answer this "in general" instead of being specific to one size plant. Light seen and perceived with the human eye is measured in Lumens. There is an ideal amount of lumens for growing and a minimum amount of required lumens. The very minimum amount of light required for smaller sized plants grown is around 3000 lumens per square foot. Let me put emphasis on "minimum amount" of light. However, that's not 100% exactly accurate, since although you may have a 10,000 lumen light, the amount of light that reaches the plant varies with the distance between the light and plants, and the reflectivity of the grow area. The ideal amount is somewhere around 7000-10,000 lumens per square foot for average sized plants. As long as the plants do not show burn, as much light can be used as you want to use. (Note, the sun produces about 10,000 lumens per square foot, on a sunny mid summer day).
Contracy to "talk" you CAN have too much light.)
OK, you need at a bare rock bottom minimum to keep them alive, of 3000 lumens per sq ft. 10,000 lumens would be great, would be equal to the sun's light and way more than ample and sufficient.
Lets split the difference down the middle and say you need 6000 to do a great grow.
You have 3 X 4 = 12 sq ft, so you need 12 X 6000 = 72,000 lumens for average, and
12 X 3000 = 36,000 lumens for rock bottom bare minimum.
The 68 watt CFLs are going to be about 60 to 70 lumens per watt, and its easy to divide 60 into 36,000 so at bare minimum for your 12 sq ft, you need 6000 watts.
12,000 watts would be way over too much, equal to the suns light so I 'd try for the 36,000 lumens, or 600 watts for 12 sq ft.
If those 68s can provide 70 lumens per watt, then 36,000 divided by 70 = 514 total watts, again at bare minimum requirement.
so the answer is you need at least between 514 and 600 watts, divided by 68 = 7 or 8 of the 68 watt bulbs.
And remember, you need the DUAL spectrum of both cool white and warm white, or red and blue spectrum, or high and low kelvins.
I hope you read the link to the CFL Tutorial, the first page at least.
Good Luck with your grow, bro.
How much light is needed for growing?
Depends on the size of plant you are trying to grow. I'll try to answer this "in general" instead of being specific to one size plant. Light seen and perceived with the human eye is measured in Lumens. There is an ideal amount of lumens for growing and a minimum amount of required lumens. The very minimum amount of light required for smaller sized plants grown is around 3000 lumens per square foot. Let me put emphasis on "minimum amount" of light. However, that's not 100% exactly accurate, since although you may have a 10,000 lumen light, the amount of light that reaches the plant varies with the distance between the light and plants, and the reflectivity of the grow area. The ideal amount is somewhere around 7000-10,000 lumens per square foot for average sized plants. As long as the plants do not show burn, as much light can be used as you want to use. (Note, the sun produces about 10,000 lumens per square foot, on a sunny mid summer day).
Contracy to "talk" you CAN have too much light.)
OK, you need at a bare rock bottom minimum to keep them alive, of 3000 lumens per sq ft. 10,000 lumens would be great, would be equal to the sun's light and way more than ample and sufficient.
Lets split the difference down the middle and say you need 6000 to do a great grow.
You have 3 X 4 = 12 sq ft, so you need 12 X 6000 = 72,000 lumens for average, and
12 X 3000 = 36,000 lumens for rock bottom bare minimum.
The 68 watt CFLs are going to be about 60 to 70 lumens per watt, and its easy to divide 60 into 36,000 so at bare minimum for your 12 sq ft, you need 6000 watts.
12,000 watts would be way over too much, equal to the suns light so I 'd try for the 36,000 lumens, or 600 watts for 12 sq ft.
If those 68s can provide 70 lumens per watt, then 36,000 divided by 70 = 514 total watts, again at bare minimum requirement.
so the answer is you need at least between 514 and 600 watts, divided by 68 = 7 or 8 of the 68 watt bulbs.
And remember, you need the DUAL spectrum of both cool white and warm white, or red and blue spectrum, or high and low kelvins.
I hope you read the link to the CFL Tutorial, the first page at least.
Good Luck with your grow, bro.
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