Practical light checks at home
Plant light measurement guides
Learn to measure lux at leaf height, compare window and shelf spots, and understand lux, PPFD and phone sensor limits.
LumaLeaf guide · Reviewed
Choose the question you have today
New to measuring? Start at leaf height. Moving a plant? Compare its current spot with a window or shelf. Interpreting a grow-light number? Read the unit guide before attempting a lux-to-PPFD conversion.
Each guide follows a repeatable routine: keep measurement conditions consistent, compare records rather than a single number, and observe the plant after a change. There is no universal lux target for every plant and no diagnosis from one reading.
- How to measure plant light at leaf height with your phone
A repeatable lux-check routine: find the sensor, measure where leaves sit, record the conditions and compare readings without treating one number as a diagnosis.
- Compare window and shelf light before moving a houseplant
Compare two real plant positions with the same phone and timing, keep a simple log, and avoid choosing a spot from one bright midday reading.
- Lux vs PPFD: what a phone light sensor can and cannot tell you
Understand lux, PPFD and DLI before comparing grow lights. Learn why a single conversion factor or phone reading cannot provide a calibrated plant-light assessment.