Lighting an orchid closet - fluorescent or LED? Otherwise?

[DavidCampen]

Originally Posted by Magnus A

I am now testing a LED panel with white light that gives 110 lm/W. As T5 fluorescent with good spectra give about 75-80 lm/W (OSRAM DULUX® L LUMILUX®) the difference is significant.

LED technology moves FAST!

We are talking about lights for plant growth not human vision. Lumens is a fairly useless metric for evaluating lights for plant growth. The lumen metric is strongly weighted to human vision. You could have an LED emitting 200 lumens per watt of 555 nm light and it would be less efficacious for plant growth than an LED giving 20 lumen per watt at 660 nm.