Plant Light
Lumens and watts needed for the plant's light level.
About Plant Light
The chosen light tier sets a foot-candle target, which is multiplied by the floor area and divided by fixture efficiency. Sun-loving plants stretch and pale in shadow, so matching intense light to the right plants keeps them unrugged.
Formula
Plant Light
Lumens = area x foot-candles; LED watts = lumens / 90
- 90
- Approximate lumens per watt of an LED grow fixture
Worked example
With the default values below, Plant Light returns Target Intensity of 1,500. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Light levelone of Low (tolerant), Medium (most houseplants), High (sun lovers)
- Medium (most houseplants)
- Area to coverminimum 0.1 sq ft
- 10 sq ft
Results
- Target Intensity
- 1,500 fc
- Lumens Needed
- 15,000 lm
- LED Wattage
- 166.7 W
Step by step
- 1Values used
- 2Plant Light
- 3Target Intensity= 1,500 fc
- 4Lumens Needed= 15,000 lm
- 5LED Wattage= 166.7 W
Assumptions and limits
- The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Plant Light calculated?
Lumens = area x foot-candles; LED watts = lumens / 90 The chosen light tier sets a foot-candle target, which is multiplied by the floor area and divided by fixture efficiency.
Why does Plant Light matter?
Sun-loving plants stretch and pale in shadow, so matching intense light to the right plants keeps them unrugged.
What values do I need to enter?
This calculator takes 2 inputs: Light level, Area to cover. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.