Packera ganderi is a rare species of flowering plant in the aster family known by the common name Gander's ragwort. It is endemic to southern California, where it is known from a few occurrences in San Diego and Riverside Counties. There are an estimated 4000 plants in existence, but this number varies year to year because the plant becomes more abundant after its habitat burns in wildfires. It is a native of the fire-prone California chaparral plant community, where it grows in gabbro rock outcrops.