Green Guerillas is a non-profit organization that "uses a unique mix of education, organizing, and advocacy to help people cultivate community gardens, sustain grassroots groups and coalitions, engage youth, paint colorful murals, and address issues critical to the future of their gardens." The roots of the program go back to 1973, when Liz Christy, a Lower East Side artist, gathered friends and neighbors to transform a vacant lot into a vibrant community garden. This action sparked the modern community gardening movement in New York City and led to the formation of Green Guerillas, which now offers assistance to over 600 community gardens.

Green Guerillas' goal is to help gardeners cultivate and manage community gardens that thrive as parks, urban farms, and outdoor community centers.

-Green Guerillas holds annual plant and material giveaways and offers ongoing horticultural assistance to dozens of community garden groups and hundreds of gardens throughout the city.
-Green Guerillas also helps community gardeners to get funding for their projects. In the past few years alone they have helped community gardeners obtain over $35,000 in direct grants from foundations and council people – and there are more grant funds in the pipeline.
-Through their Harvest for Neighborhoods campaign Green Guerillas helps 30 Bedford-Stuyvesant community garden groups grow more fresh healthy food, distribute it in their historic Brooklyn neighborhood, and come together as a community of urban farmers.