Grow Lights: What is a Quantum Flux Meter?

I use my quantum flux meter to make decisions about which lamps I’ll use to grow which plants, and at different stages of development.

Don’t confuse a quantum flux meter with standard visual light meters or Watt meters. Using a Watt meter and a standard light meter that measures lumens, you can calculate LPW outputs for a given lamp, which helps you assess efficiency.

You can also use standard light meters to measure footcandles of light. But remember that standard light meters, which measure in footcandles or lux, are not accurate for determining plant light needs.

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