Free Interactive Tool
Light Meter
Convert lux readings to plant-friendly recommendations. Get species-specific placement advice based on your light conditions.
Light Meter Guide
Convert lux readings to plant-friendly recommendations
Use a lux meter app or device to measure light at plant leaf level
Light recommendations based on compiled botanical research • Seasonal variations affect light intensity • Measure at leaf level
Understanding Light Categories
Very Low
< 500 lux
Interior rooms, far from windows
Best for: Snake plants, ZZ plants
Low
500–1,000 lux
North windows, deeply shaded
Best for: Peace lilies, pothos
Medium
1,000–3,000 lux
East windows, 3–5 ft from south
Best for: Calathea, philodendron
Bright Indirect
3,000–8,000 lux
Near east/south with sheer curtain
Best for: Monstera, fiddle leaf fig
🏛️ How this tool works
Methodology, data sources & the Building 1411 apparatus
How this tool works
Methodology, data sources & the Building 1411 apparatus
Light requirements are derived from the Plant Grail knowledge base, compiled from horticultural research and documented indoor growing conditions. Measurements assume typical home environments with standard windows. Lux ranges are mapped to four light categories (Very Low, Low, Medium, Bright Indirect) with species-specific thresholds.
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