Assuming that you don't already know who owns the plot, check with City Hall before you start digging. If it's public property, you can apply to the Parks Department for approval. ACGA's helpful guide suggests that you make sure the site gets at least six hours of sunlight a day, consider past uses of land (in case there's a chance of contamination), and do a soil test. Also make sure that you have easy access to water and, especially if you plan to be a city-run garden, wheelchair access. If it is privately owned, your best bet is to identify the owner and ask for either a longer-term lease (preferably at least three years), or free, temporary use of the lot. For either, you will likely have to agree to assume all liability—and even then it might be a tough sell.
While the cost of your garden will depend on the size, design (Want ideas? Check out the White House garden plans), and how many in-kind donations you receive from local businesses, the Parks Department says to estimate $20 per square foot in construction costs. Urban Harvest, a community-garden nonprofit in Houston, provides a helpful list of items to include when planning your budget. If the cost becomes daunting, you can start looking for funding elsewhere. The U.S. Department of Agriculture has a competitive grant program for Community Food Projects, granting nonprofits approximately $5 million in 2009. And more funding may be on the way. The Community Gardens Act, a bill to provide additional funds for establishing community gardens, was introduced last month by Rep. Jay Inslee, D-Wash.
Since there are already so many community gardens in the Bay Area, make sure that yours actually fills a need (and that people will help you!). Send flyers around your neighborhood and approach established groups, such as community centers or churches. Talk about your idea at a community meeting. Congress proclaimed August "National Community Gardening Awareness Month"; go ahead and use the publicity to help drum up support for your cause.
Starting a community garden is no easy task, so no one will fault you if this sounds like more than you bargained for. In that case, you can get involved with an existing community garden, such as Alemany Farm in southeastern San Francisco or Free Farm Stand, a volunteer-run organization that offers backyard produce free to the public (especially low-income residents of the Mission District). Or join a group that is harvesting and donating food from local fruit trees, such as Village Harvests or SF Glean.
Finally, if you have backyard space in addition to the ugly vacant lot you'd like planted, consider contacting MyFarm, one of the few for-profit urban gardening groups. MyFarm will design, plant, and maintain an organic vegetable garden in your own backyard for an installation cost and modest weekly charge. With that kind of service, not even I would be able to kill the tomatoes.
Do you have a real-life do-gooding dilemma? Please send it to firstname.lastname@example.org, and Sandy will try to answer it.