The population outgrew ability of farms to feed everyone in the early 20th century . MNN : Farms of America from the 1930s and '40s . Growers started using more chemicals , etc . J.I . Johnson popularized organic farming in the 1960s and ' 70s . Sales of organic products continued to rise .
The population outgrew ability of farms to feed everyone in the early 20th century . Growers started using more chemicals , etc . J.I . Johnson popularized organic farming in the 1960s and ' 70s . Sales of organic products continued to rise .