featur
spectral light
Lighting is one of the most critical factors
when it comes to growing healthy plants.
Whether growing indoors or outdoors,
color temperature can have a major
impact on your plants’ height, leaf size,
and harvest. Not all plants are the same
and they may react differently to different
color spectrums; however, some principles
affect all the plants in your garden.
L
HOW
SPECTRAL
LIGHT
INFLUENCES PLANT GROWTH
by Monica Mansfield
ight can be expressed as a wave.
Imagine the ripples that form on a pond
when you throw a pebble into the water.
This is very similar to what light waves
look like. The size of the waves, or wave-
lengths, vary depending on where the color
of the light falls on the electromagnetic
spectrum. Red light such as radio, micro-
wave, and infrared wavelengths are wide,
long, and contain less energy. Violet light
such as UV, X-rays, and gamma rays are
short, narrow, and high energy.
Kelvin Color Temperature Scale
10,000K —
— 10,000K + = Blue Sky
9.000K —
8,000K —
7,000K —
6,000K — — 6,000K = Cloudy Sky
5,000K — — 4,800K = Direct Sunlight
4,000K —
3,000K —
2,000K —
1,000K —
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feature
— 7,000-7,500K = Cool White
— 5,500-6,000K = Day White
— 4,000-4,500K = Natural White
— 4,000K = Clear Metal Halide
— 3,000K = 100W Halogen
— 2,800K = 100W Incandescent
— 2,700-3,200K = Warm White
— 2,200K = High Pressure Sodium
— 1,900K = Candle