Most gardeners know lumens to be the “measure of the total ‘amount’ of visible light emitted by a source.” What they often do not know is that this “visible light” only refers to light that is visible to the human eye with no regard to the distribution of that light energy over the spectrum. Why does this matter? Imagine three lamps: let these lamps be red, blue, and green, and let each emit the same number of watts of optical energy. On a lumen scale, the red and blue lamps would have a much … [Read more...] about Plant Lighting Pt 1: Plants see PAR, humans see Lumens
Lumens
Indoor Grow Lights: Bringing Couches and Tomatoes Together Part Dos
The T-5 Bulb: Friend of Plants and Wallets Everywhere The first glance at a T5 fluorescent bulb will elicit snickers from the unaware. Eyes used to the bulkiness of a T8 or T12 fluorescent grow bulb will look at the slender T5 and ponder if the lighting industry has a cog loose. Ecologically speaking, Al Gore would pin a medal on the lithe grow light. It's constructed with 40% less glass than the T8 as well as 30 % less phosphor. The T5 contains only 3 mg of mercury, which is 70% less … [Read more...] about Indoor Grow Lights: Bringing Couches and Tomatoes Together Part Dos
