Community gardens are critical ecological infrastructure in cities providing an important link between people and urban nature. The documented benefits of community gardens include food production, recreational opportunities, and a wide number of social benefits such as improving community stability, reducing crime, and physical and mental health benefits. While much of the literature cites community gardens as providing environmental benefits for cities, there is little empirical evidence of these benefits. Here we examine the stormwater runoff benefits of community gardens by comparing two methods to estimate absorption rates of stormwater runoff in urban community gardens of New York City. The first method uses general land cover classes as determined by a land cover dataset; the second methods adds a land cover specific to community gardens — raised beds, typically used for food production. We find that in addition to the stormwater mitigation performed by pervious surfaces within a garden site, community gardens in New York City may be retaining an additional 12 million gallons (~45 million liters) of stormwater annually due to the widespread use of raised beds with compost as a soil amendment.