Ann: AusCann Joint Venture Harvests Second Crop in Chile, page-35

Canopy Growth Corp
250,000 square foot greenhouse should be able to produce around 10,000 kilograms of marijuana annually, which at an average sale price of C$8 a gram could bring in C$80 million.
420 grams per square metre
In Arizona, Colorado, California, and Oregon, cannabis is being cultivated in greenhouses in excess of 250,000 sq. ft. that are capable of yielding more than 50,000 pounds of flower.
2kgs per square metre
I dont know how much gibberish you get per square metre