Scientists compared the strawberries grown on 26 neighboring farms in Watsonville, Calif., and found that organic berries had juicier nutrition data and left the soil healthier.

The study, published Sept. 1 in the online peer-reviewed journal PLoS ONE, analyzed the DNA as well as 31 chemical and biological properties of the soil at 13 organic and 13 conventional strawberry farms that were often separated by only a road. It also compared taste, nutrition and quality of three strawberry varieties.

The study found that the organic strawberries had higher levels of antioxidants and vitamin C. They also had a longer shelf life. “The strawberries had to fend for themselves out in the wild by producing natural compounds that slow down the growth of fungi and viruses, and that benefit carries on after the strawberries are picked,” explained Charles Benbrook, chief scientist at Boulder, Colo.-based The Organic Center, which partially funded the study, along with the USDA and the Department of Energy Office of Biological and Environmental Research.

The organic soils had more enzymatic activity and micronutrients and, according to the DNA analysis, more genetic diversity than the conventional soils—an important consideration, Benbrook said, because “each organism helps keep the others in check and from reaching a level that could damage the plant.”

In addition, the organic version of one berry variety—Diamante— was judged to taste sweeter and have a better appearance than its conventional counterpart.

But the study wasn’t entirely sweet on organics. Tasters liked conventional San Juan strawberries better than organic ones, and taste tests for Lanai berries came to a draw. The conventional berries were 13.4 percent larger, and had more potassium and phosphorus.

“For potassium, you would be looking at potatoes or bananas, which are high carriers,” noted John Reganold, a professor of soil science at Washington State University, and the study’s lead researcher. “People don’t eat strawberries for potassium and phosphorous. I think it’s more significant that we have more of the things people buy strawberries for— the vitamin C and the antioxidants.”