In the spring wildflowers are everywhere in the Bay Area and while nearly every park has some blooms (even the freeways bloom around the Bay) here and there a few parks stand above the crowd. Many other parks also have wonderful displays including: Almaden-Quicksilver, Foothills, Windy Hill, Point Reyes, Mt Tamalpais, Mt Diablo, and Mission Peak. Keep in mind too that after the dominant displays in the hills are over in May, deep in the redwoods beautiful redwood sorrel and foxgloves quietly come to life extending the season well into July.
Russian Ridge Open Space Preserve
Russian Ridge is a popular park in any season. It has rolling green hills with sweeping views over the redwood studded Santa Cruz Mountains which continue out to the blue waters of the Pacific Ocean. When the wildflowers pop out though your eye might stray awhile from the grand landscape down to the beauty just below your nose. Each April Russian Ridge lights up with powerful displays of Owl's Clover, Checkerbloom, Fiddlenecks, California Golden Violet's, and several kinds of Lupine every year. Some of the best displays can be found on the slopes of Borel Hill but patches are all over the park. The combination of grand views, quaint forests, and a strong wildflower showing makes Russian Ridge one of the first destinations on any wildflower spotters list.
Edgewood Park & Preserve
The king-daddy of wildflower parks. Edgewood explodes with color and life every spring putting on dazzling displays of gold and purple which cover the hillsides in the largest, densest, and most diverse showing of wildflowers in the Bay Area. The hills above the Serpentine trail offer the best showings, but any of the clearings will be covered with wildflowers. Unfortunately though the park happens to be situated close to the noise and polluted air of Hwy 280 which draws from the serenity of the park considerably. Truth be told Edgewood would actually be a pretty mediocre park if it were not for the jaw dropping show it's wildflowers put on every spring.
Santa Teresa County Park
Tucked away in South San Jose out where the sprawling suburbs finally give way to undeveloped country lies an unassuming trailhead off Fortini Road. Two steps up the trail you'll discover slopes covered in the orange and gold of Poppies, Goldenfields, and Fiddlenecks all backed up against commanding views of a mostly pristine valley and the highest peaks in the Santa Cruz Mountains beyond that. Although the Fortini trail (the best wildflowers are found along this trail) is fairly short, a larger loop up Coyote Peak offers increasingly grand views and continually impressive displays of wildflowers. The wildflower showings in Santa Teresa are not as grand as in Russian Ridge and Edgewood however you'll likely have this little gem of a park to yourself free from the roar of cars and buzz of city life.
Briones Regional Preserve
From the slopes of Mount Diablo to Mission Peak there blooms an abundance of wildflowers in the green grassy hills of the East Bay. What the East lacks in blazing displays and a rich diversity of flowers though it makes up for the consistency and ease in which you can find them. Small patches litter the hills and steep valleys and the best place to enjoy them is most likely Birones Regional Park who's rolling green hills are packed with glowing displays of nearly every kind of wildflower.Briones Photo by aar0n5150 (on flickr)
Angel Island State Park
Angel Island may not have the most impressive displays of Wildflowers in the Bay Area but they are set against one of the most stunning backdrops in the region. Poppies flutter in the wind on the steep slopes of Mt. Livermore, the highest point on the island, while Lupines dot the coastal flats sitting amongst the relics of gun batteries which overlooking the choppy waters of the San Francisco Bay. With views in all directions there isn't a boring spot on the island. The west shore of the island though is particularly alive with blooms of Lupine and also benefits from views of the Golden Gate Bridge and Marin Headlands behind it.