SPIN stands for Small Plot IN-tensive. The Spin Farm-ers know of what they speak—two of the creators gave up traditional farming to operate Wally's Urban Market Garden, a sub-acre operation on 25 rented residential backyard garden plots in Saskatoon, Saskatchewan. The 25 yards equal just one acre.
The major precepts simple: Relay cropping, which mixes varying plants within a space, and choosing a profitable crop based on your local market. City growing also provides a more controlled environment with fewer pests, better wind shelter and a longer growing season.
SPIN uses a series of PDF guides, most cheaper than a paperback. A complete series is also available for $83.93.
You even get personal consulting and a support group via email.