Looks great!

Why are you using light fixtures that bock daylight in a greenhouse? Is it because your greenhouse is in the shade? I ask because, most typically, people with grow lights in greenhouses use fixtures, e.g., spot lights, that do not cast large shadows so that the electric light supplements the daylight. Also, what kind of heating do you use?

In my case, my lean-to greenhouse receives plenty of sunlight in front and less near the back. I have adequate growing space in front, but, I use all electric lighting in back because I can grow extra short seedlings by making the dark period temperature higher than the light period temperature. I accomplish this by having the lights off during the day and on during the night. My plants, mostly tomato, some pepper and canna seedlings, are in a growth chamber that blocks, maybe, 99.9% of the daylight. Also, I have an open flame gas heater that enriches the air with carbon dioxide mostly during the night which is another good reason to have the lights on during the night (Otherwise, that free CO2 would go to waste). Depending on your exact situation, you might want to consider doing the same.

Aruzinsky,

Great point and info! They all make huge sense.