This might be a controversial thing to say here, but I think that clandestine marijuana farmers are really heavily pushing the limits of urban agriculture. The

This might be a controversial thing to say here, but I think that clandestine marijuana farmers are really heavily pushing the limits of urban agriculture. The things you're working for when growing pot: 1) A minimal energy footprint. A giant power bill is a dead giveaway that you're running grow lamps 2) Maximum plant density -- lots of plants close together is good for both absorbing light and using space. More plants = more money. Obviously that isn't what this person is growing, but I find pot growers to be an interesting bunch. They're ag-hackers, and they seem to be really good at it, and really good at trading information about it.