Does it look like these are ready to switch from 600w MH to 600w HPS? They are auto flower Sour Diesel, and they are nearing the end of week 4 from seed. LST used aggressively.
Looks great! If you can try to look for the start of the pistil on the plant, look directly at a node and see if you can spot the calyx, this will look like 2 small ovals. If they have white hairs protruding from them, it would be the time to switch. Alternatively if you wanna push your plants to a larger harvest, treat them as if they are still vegging for another week or so until most of the nodes show long white hairs. This will delay the time they will be ready for harvest but allow for a bigger one. Once you make the switch do not go back, you might over stress your plants.
Thank you much!