DUE TO LACK OF TRUE KNOWLEDGE, THIS MAY SOUND COUNTER INTUITIVE BUT YOU SAVE OVER $50 WITH 1000 WATT LAMPS BY VEGGING LONGER DAYLIGHT HOURS.
First it ALSO depends on many factors, Biotic factors (nute schedule, genetics, nute type, etc) and abiotic factors (pests, temp, wind, hunidity etc. Then...