How Does Blue Light Affect Plant Growth?

November 3, 2018

Blue light helps control excessive stem elongation, or stretching toward light. It influences how chloroplasts move around in plant cells and helps regulate stomatal opening.

Cannabis plants in a vegetative (non-flowering) state.
PC: Dan Heims

You can grow some crops (short-lived ones such as microgreens) using only blue light, which supports ongoing vegetative growth, but don’t expect any flowers in certain types of plants--such as cannabis.

Gardening Under Lights Book

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