GlenCalc

Daily light integral calculator

DLI is the total light plants receive in a day, in moles per square meter. Grow lights list PPFD in µmol/m²/s at a hanging height.

Your answer

Daily light integral17.3 mol/m²/day

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How we worked it out

Updated as you change the numbers.

  1. DLI = PPFD × hours × 3,600 s ÷ 1,000,000 = PPFD × hours × 0.0036.

Method and assumptions

Leafy greens and herbs generally do well around 12 to 17 mol/m²/day; fruiting crops need 20 to 30 or more. Light intensity falls off as the light is raised, so measure PPFD at the plant tops.

Questions

What DLI does 300 PPFD for 16 hours give?

17.3 mol/m²/day.

Sources

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