Dated 2010..........
Some say the average is now 130 grams per sq foot...............
Yield estimates are grounded in Toonen et al.’s (2006) study of 77 illegal, indoor
growing operations in the Netherlands. They found a median planting density of 15
plants per square meter, or 1.4 plants per square foot, and an average yield of 1.2 ounces
of saleable material per plant per harvest.6
That translates to 0.105 pounds per square
foot per harvest or 2.625 pounds per 25 square feet per harvest. Combining this with the
$600 figure derived above, the materials and consumables cost per pound is about $225
per pound.
https://www.rand.org/content/dam/rand/pubs/working_papers/2010/RAND_WR764.pdf