What is Lux?
Understanding Lux Vs. PAR
Manufacturers have little to say about lux or lumens when discussing grow lights. This is because lux measures the intensity of light visible to the human eye. However, the wavelengths that plants use for photosynthesis are less visible to our eyes. So instead of boasting about illuminance, grow light manufacturers emphasize the amount of PAR—or photosynthetically active radiation—given off by their lights.