I can think of at least four commercial grow operations within about six miles of the house. A couple of them are in greenhouses, albeit they are behind high walls with barbed wire and cameras, and the others are in business parks in the usual concrete tilt-up buildings. I ride my bicycle by them all the time, and I do not smell anything, so perhaps the state/county/city require some sort of odor control, since I have been inside two of them and the smell inside was very noticeable.