GrowDirector PAR SensorA PAR sensor measures the quantity and quality of light available to plants within a growing environment. PAR stands for photosynthetically active radiation, and these sensors can provide valuable data on the intensity and spectrum of light that plants require for optimal growth and development. PAR sensors work by detecting the number of photons in the range of 400 700 nm, which is the range of light that plants use for photosynthesis. The sensor