1. What is Daily Light Integral (DLI)?

Definition: DLI measures the total amount of photosynthetically active radiation (PAR) delivered to plants over a 24-hour period.

Purpose: It helps growers optimize light conditions for plant growth in greenhouses, indoor farms, and research settings.

2. How Does the DLI Calculator Work?

The calculator uses the formula:

Where:

• \( DLI \) — Daily Light Integral (mol/m²/day)
• \( PPFD \) — Photosynthetic Photon Flux Density (μmol/m²/s)
• \( Hours \) — Duration of light exposure (hours)

Explanation: The formula converts instantaneous PPFD measurements into total daily light exposure by accounting for time.

3. Importance of DLI Calculation

Details: Proper DLI ensures optimal plant growth, flowering, and fruiting. Different plants have specific DLI requirements.

4. Using the Calculator

Tips: Enter PPFD (from a PAR meter) and daily light hours. Typical values range from 5-60 for PPFD and 12-18 for hours.

5. Frequently Asked Questions (FAQ)

Q1: What's a good DLI for most plants?
A: Most crops thrive at 12-30 mol/m²/day, but exact needs vary by species and growth stage.

Q2: How do I measure PPFD?
A: Use a quantum PAR meter to measure light intensity at canopy level.

Q3: Why is 3600 used in the formula?
A: This converts seconds to hours (60 seconds × 60 minutes).

Q4: What's the 1,000,000 divisor for?
A: It converts micromoles (μmol) to moles (mol).

Q5: Can I calculate DLI for sunlight?
A: Yes, but sunlight PPFD varies throughout the day, so use average values or integrated measurements.