Sugar beets, kale, broccoli and calendula poke out between rocks on Blue Marble Acres’ gravel parking lot, which overlooks an expanse of rolling hills on Point Reyes-Petaluma Road. Co-owner George Gund lovingly pinches the yellow petals of a calendula flower, explaining that the plants grew on their own from seeds that blew onto the lot. “This is a nice example of how really fertile the soil is with no help at all,” he said.