With a 600 watt HPS light, the best you could possibly hope for is around 1-1.5 lbs of cured and dried cannabis (3’x3’ canopy). These numbers are true if you’ve done everything right from start to finish, grew a high yielding strain, co2 injected and followed all the important guidelines here on the Perfect Grower knowledge section. Realistically, 0.7-1 lb per 600W fixture is a more conservative estimation.
With a 1000 watt single-ended HPS light, it’s possible to get upwards of 2 pounds with the proper environment, genetics, substrate management and feeding intensity. Realistically, 1 lb per single ended 1000 watt light is average estimate and still considered a successful harvest (4’x4’ canopy). With a 1000 watt double ended HPS light and properly filled 5×5 canopy, upwards of 3 pounds a light is possible. A good average for most genetics is closer to 2.
With LED lighting, results can vary depending on the quality and spectrum of the LED fixture itself. Most low to mid-range LED lights will under-perform compared to their HID counterparts. LED lighting has a lot of potential for the future of cannabis cultivation but the current industry is filled with a lot of uncertainty and variability.