Quantum sensors measure light energy at the specific wavelengths plants actually use for photosynthesis. Research indicates that older lux and foot-candle meters could have error rates up to 45% when used to estimate light quantum available for plant growth. Start taking more meaningful light level measurements yourself with a low-cost quantum meter.

All quantum meters here measure Photosynthetic Photon Flux (PPF) as µmol m-2 s-1 for Photosynthetically Active Radiation (PAR) in the range of 400 to 700 nm. The 3 or 6 sensor handheld bar on this Quantum Light Meter provides a spatial averaged PAR (Photosynthetically Active Radiation) reading. PAR averages are a more comprehensive indicator of light quantity reaching your plants, and serve as a powerful tool to manage lighting.

Quantum meters can be used in the field, laboratory, above or below plants, in growth rooms and greenhouses. The meter approximates radiation between 400 and 700 nanometers(PAR) as umol m-2s-1.

Click to view light guidelines for popular greenhouse plants.