💡 The light your plants need depends on their growth stage. Leafy greens prefer a gentle, vegetative spectrum, while heavy fruiting plants require intense light for long periods to produce a harvest.Â
Lighting Requirements Matrix
PPFD (Photosynthetic Photon Flux Density) measures the actual amount of plant-usable light hitting a square metre of the plant canopy every second.
Plant Profiles & Pro-Tips
1. Leafy Greens & Herbs (Low to Medium Intensity)
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The Profile: Lettuce, spinach, basil, and mint have low energy thresholds. If you give them too much intense light, they will experience leaf scorch or bolt (go to seed and turn bitter).
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Hanging Distance: Hang your LED grow light higher up—roughly 45 to 60 cm above the plants.
2. Strawberries (Medium Intensity)
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The Profile: Strawberries need a steady, moderate amount of light to sweeten their berries. They are highly sensitive to day length; changing their light timer from 14 hours down to 12 hours tells the plant that autumn is coming, triggering it to flower.
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Hanging Distance: Keep your lights roughly 40 to 45 cm away from the canopy.
3. Tomatoes, Capsicums, & Cucumbers (High Intensity)
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The Profile: These are high-energy crops. If their light is too weak, they will grow long, thin, spindly vines that lack the structural strength to hold heavy fruit, and their flowers will simply drop off.
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Hanging Distance: Position your grow lights close—about 30 to 40 cm above the top leaves. You will need to constantly raise the lights upward as these giant vines climb.
How to Measure Light Without Expensive Gear
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Use Your Smartphone: Download a free light-meter app.Â
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The Method: Hold your phone camera flat at the exact height of your plant's top leaves, facing directly up at the grow light. The app uses your camera sensor to estimate your PPFD reading instantly.
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