by Meg Stout
(Northern Virginia)
I'm just in a townhome, but I'm able to have a 200 gallon aquaponic system out back. My current garden gives me about 40 ft^2 of growing space, but I have a design that would increase that to more than 100 ft^2.
With an aquaponic garden, you only need 10-20% of the water you'd need for a traditional garden because the water is recycled from your fish tank to rock-filled grow beds (no soil required). To make the water flow properly, your grow beds are elevated (thank you, says my back), and you can set up a garden on pavement, if that's all you have.
The fish produce the ammonia you need (no petrochmemical fertilizer) and can be edible (catfish, bluegill, perch, tilapia, trout) or ornamental (koi, goldfish). In a true emergency, you can use the water in your system for drinking if you purify it properly (hand pump/filter units, solar heater pasteurization, etc.)
By maintaining a garden in regular times, you get a well-developed ecological infrastructure that can convert the fish ammonia into nitrate - a bacteriological system that takes a month or more to develop if you're starting completely from scratch, say if you were to only be reacting to an emergency (hello furlough...)
Because I keep my garden under a hoop house frame (made from EMT electrical conduit), I can put up shade cloth in summer to keep things from scorching and plastic in winter to make a greenhouse for retaining warmth.
I've had my backyard garden in place for two years here in the DC area and it's never frozen over, even without using solar heaters, electrical/propane heaters, or rocket mass heaters. I have plans to add passive solar heating/cooling and attach my rocket mass heater (finally...) merely because fish and winter plants will produce faster if kept a tad warmer.
While an aquaponic garden isn't as inexpensive to create as a soil garden, it's a way to produce abundant amounts of safe food. And long-term effort and cost is minimal.