FlytrapCare Carnivorous Plant Forums

I'd like to know the answer if anyone knows. Or one hour of sunlight = ? hours of fluorescent light, etc.

Thanks

I've also been wondering that. I have two T5 tubes running for 12 hours every day and wonder how much light that is in comparison. Think I'll keep an eye on this thread!

Yeah you should! All I know is that 16 hours of artificial light are good for VFT, that 4 hours of sunlight keep VFT barely alive and that 1 hour of sunlight > 1 hour of artificial light.

This is a very tough question since there are so many variables.

With artificial lights the amount of PAR(photosynthetically active radiation) that reaches a plant depends on the type of light(T12, T8, T5), the reflectors used, the ballast used, the distance from the leaf surface, and other variables.

With the Sun PAR varies depending on season, loacation, environmental factors(weather, pollution, etc), and others.

So it's kind of an apples/oranges thing. 6 hours of direct Sun at the equator is not the same as 6 hours of direct Sun in Canada because the angle of the light reaching the surface plays a big role in how much is reflected.

So 16 hours at 6 inches from a T5HO with quality reflectors may equal X hours of direct sun in the North-West US but only 1/4X hours of direct Sun in Northern South America.

Thanks parker679.

Parker is right. This is a though question.
But there isn't UV and IR in artifical light which is are in natural sunlight. Theoritically you can calculate how much light can you give to your plant. There is a number in your light bulb that how many lumen/square meters could it radiate.

BUT it's much much less than natural sunshine.

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux. Bright sunlight provides illuminance of approximately 100,000 lux or lumens per square meter at the Earth's surface. The total amount of energy received at ground level from the sun at the zenith is 1004 watts per square meter, which is composed of 527 watts of infrared radiation, 445 watts of visible light, and 32 watts of ultraviolet radiation.

I guess I'll try to provide sunlight as much as I can and fill the rest with artificial light.

Last summer I used:

-2 GE T8 Daylight bulbs
-2700 lumens each
-7-8" from the soil
-Fixture with a reflector

Under this setup, 16 hours was plentiful for them. So my estimate is that it was equal to a full summer's day of sunshine or more. I went up to 18 hours during the longest days. Going into late fall I think I was down to 12-13 hours before they started to die back a little. They were still growing but couldn't support as many leaves at once.

I've found a site with a lot of information...

http://www.waynesthisandthat.com/fluorescent.html

I don't know the fuy but he have also a good site about VFTs

http://www.waynesthisandthat.com/venusflytrap.html