Has anyone actually made measurements of the lux or foot candle readings they are growing their plants under, or plants in the wild.
The few mentions I have found led me to illuminate mine at about 10K lux when I recently started using metal halide as a supplementary winter light in my greenhouse.
In some plants this has led to leaf reddening (suprisingly rajah - I thought this liked high light), others e.g. jacquelinae & lowii nothing at all.
I am going to leave them to adjust, its just interesting they seem to perceive this as high light when this is less than 1/10 of summer/tropical sunlight