Glossary · Plant care

Light meter for plants.

A light meter for plants is a device that measures the amount of light in lux (or foot-candles) at a specific spot, so you can match the reading to each plant's preferred range. Houseplants typically need 50–2,500 foot-candles depending on the species: succulents and ficus want 1,500–5,000+ FC (full sun); pothos and philodendron tolerate 75–500 FC (medium light); ferns and calatheas thrive at 50–250 FC (low light). The iPhone camera, used through an app like Tazart, measures lux directly without buying a separate meter.

Light ranges by plant type.

Light level Lux Foot-candles Plants
Bright direct sun 10,000 – 50,000+ 1,000 – 5,000+ Cacti, succulents, ficus, citrus, hibiscus, bird of paradise
Bright indirect 2,500 – 10,000 250 – 1,000 Monstera, fiddle leaf fig, rubber tree, alocasia, hoya
Medium light 750 – 2,500 75 – 250 Pothos, philodendron, peace lily, spider plant, ZZ plant
Low light 250 – 750 25 – 75 Snake plant, cast iron plant, calathea, prayer plant
Too dim for most < 250 < 25 Almost nothing thrives long-term — supplement with grow lights

How to measure light without buying a meter.

The iPhone camera's exposure sensor is sensitive enough to measure lux directly. Tazart's free light meter uses it: open the app, tap the light meter icon, point at the spot you want to measure, and hold steady for 2 seconds. The reading shows in lux + foot-candles, plus a list of plants that thrive at that level.

Measure at the time of day the plant will live there — morning sun behaves differently than 4 PM sun. Take 3–4 readings across the day for the most accurate average.