It looks like the author is changing the light color and intensity throughout the day to approximate the color of sunlight. But he has a bunch of LEDs in different spatial locations…

You could make the LEDs be different colors based on location to model the light coming from that direction, at that time of day. Then you could get your plants to track.

It might take much brighter LEDs, since the relatively few sunward ones would need to really crank out the photons while most of them were more chill and bluer.