Full-Spectrum Lamps Emit All Colors of Light

March 13, 2019

Full-spectrum grow lamps, whether they skew warm or cool, will emit some percentage of all colors of light within the PAR range. Cool full-spectrum lamps will still emit some red and yellow light, but less of it. Warm full-spectrum lamps will still emit some blue and green light, but less of it.

Seedlings growing under full-spectrum fluorescent lamps.
PC: Homestead Gardens

I can grow young tomato transplants in an open space under a large eight-lamp fluorescent fixture filled with cool-spectrum lamps. As plants grow, I replace half the cool-spectrum lamps with some warm-spectrum fluorescent tubes when I want to trigger more flowering.

Gardening Under Lights Book

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