Just adding my 2 cents. I have plants in my unheated basement (55-60F) that grow with LEDs that are majority red/blue. There are about 15% of the LEDs that are full spectrum. The ~400w light covers a 4x4' grow area and growth is fairly slow due to temperature and watering only every 2+ weeks. I've never had a flower indoors and I usually just use this grow area for sustaining small plants. I have seen pstem growth of about one foot but usually just on smaller plants. I would imagine your total light wattage would need to be over 1000W to see significant growth. Personally, I must wait for spring and move plants outside since I don't want to see my electricity bill get too high!
