Start small, recommends Jo Cook, program coordinator with the Master Gardeners' Program at the University of Arizona. "A small charity-based or cooperative garden is a fun, doable choice for beginners," she says.
Find a location. Approach an organization with which you're familiar-like a church or school in your community, or even your apartment complex-to see if you can use their land. Existing organizations are likely to have a water source, which is crucial. "Most groups are thrilled someone is willing to take the time to cultivate their property," Cook says. For large-scale projects, choose a vacant lot. Contact your local city office or assessor to find a lot owner's contact information. Then inquire about having the land donated or leased for a minimal fee. Or ask the local Cooperative Extension office for suggestions. A location that's close to you is best, says Katherine Whiteside, author of The Way We Garden Now. "You should be able to reach the garden if you need to water more than usual during a drought," she says.
Spread the word. "Once you let people know you want to start a garden, you'll undoubtedly find others ready to lend a hand," says Lance Walheim, garden expert and author of Roses for Dummies. Tell your friends and neighbors, post flyers around town, or consider posting on Craigslist.org, a classifieds-listing service with Web sites in most mid-to-large cities. (Be sure to look under your city's "volunteers" or "groups" listings to find groups that are already formed, or post a request for volunteers for a new project.)
Draw up a plan. "Your fellow volunteers will have different personalities, ways of doing things, and levels of experience," says Amy Klein, executive director of Capital District Community Gardens in Troy, New York. "It's important to have a guide-no matter the garden size-to outline basic rules and procedures."
Gather supplies. You'll need seeds, starter plants, and tools like shovels and watering hoses. "You can often obtain most, if not all, supplies through donations," Walheim says. Contact your local botanical garden, search online for community gardening support organizations, and, again, talk to your Cooperative Extension office. Don't forget stores like Home Depot and Wal-Mart, which may offer less-than-perfect plants for a reduced price.
Start gardening. Your first year may be a process of trial and error, particularly if you're new to gardening, but that's half the fun, says Stephanie Cohen, author of The Perennial Gardener's Design Primer. "You're learning and can feel good about replacing dry soil or pavement with something green."