Edgewood's wildflower displays are a product of its unusual geology. The park sits on serpentine soil, a greenish rock derived from the Earth's mantle that is toxic to most plants. The species that have adapted to serpentine -- including several rare and endemic wildflowers -- face almost no competition from the non-native grasses that have overrun most of California's grasslands. The result is a landscape that blooms with extraordinary diversity and color each spring, with species like the Bay checkerspot butterfly depending on the serpentine habitat for survival.

Edgewood was not always a nature preserve. The land was slated for development before local activists organized to protect it, arguing that its serpentine grasslands represented an irreplaceable ecological resource. Their success resulted in the designation of the park as a Natural Preserve, prohibiting development and requiring management practices that maintain the serpentine grassland habitat. Today, volunteer groups conduct regular invasive plant removal to keep the rare native species thriving.

During peak bloom -- typically March through May -- the park's trails are lined with goldfields, tidy tips, owl's clover, and dozens of other wildflower species. The annual wildflower walks hosted by volunteers draw hundreds of visitors. For a region defined by technology, Edgewood offers something technology cannot replicate: beauty that depends entirely on soil, rain, and time.