From seaside daisies on the coast to poppies aplenty in Palo Alto, check out our guide to Peninsula preserves and trails showcasing the best blooms.
Peninsula native wildflowers are the harbinger of spring around here, a sight that calms us even when other ecological and climate indicators give us pause. The current year’s lack of rain hasn’t caused too much disruption for these sturdy natives. Matt Dolkas with Peninsula Open Space Trust (POST) confirms that the Peninsula’s wildflower display should be on par with other years and comments that If we receive a good soaking in March or April, we should be rewarded with a great late spring showing.
“The rain in October and December of 2021 were astounding and helped a lot, but you can feel that the grasses are struggling at a time of year when they should be at their best. A ‘Miracle March’ would be great,” says Dolkas of a month with wishful above-average rain.
Even if we don’at receive a steady stream of storms over the next couple of months, we can still rely on areas with serpentine soil, a geological and ecological phenomenon steeped in tectonic activity over millions of years, to support an endemic flower showing. This soil, composed primarily of serpentinite, is so toxic and depleted of commonly found soil nutrients that only a few species of plants can survive in it.
“Weeds and other invasive plants have a hard time in this soil,” Dolkas says. “And, as a result, what remains are the native flowers that have evolved with it. Pulgas Ridge and Rancho San Vicente, which is now part of San Jose’s Calero County Park, are great spots to see serpentine soil.”
According to Dolkas, now through mid-April is peak time for Peninsula wildflowers, so use our guide below to find fields abloom (and download POST’s 2022 guide here).
(Many people identify the swaths of yellow wild mustard blooms as a sign that wildflower season has begun, but these plants,Brassicaceae, are not native to the Peninsula and are considered an invasive species said to have been brought to the area by Spanish missionaries.)
Purchased and managed by the city of Palo Alto since the ‘70s, Pearson-Arastradero Preserve has over 10 miles of trails easily accessible off I-280 (Page Mill Road exit west). The Arastradero Creek Trail is a relatively easy, one-way 1.44-mile trail with moderate hills. Enter from Foothill Park, and pass the lake before you make the hike uphill. The gravel and dirt trail is nice and wide in most locations. There’s little shade, so go early in the season for the best showing and to avoid the heat. Very serene but watch out for mountain bikers who take advantage of the hills. Lots of sky lupines (Lupinus nanus) and California poppies (Eschscholzia californica) are visible from various spots along the route.
There are plenty of trails to explore at this Midpeninsula park, and the only way to get to where the wildflowers are is to head uphill through a narrow trail shaded by heritage oaks. It’s not a challenging climb as there are lots of switchbacks. Follow the Clarkia Trail to the Sunset Trail, and then pick up the Serpentine Trail where the serpentine soil nurtures special natives. Look for chick lupine (Lupinus microcarpus) and purple coyote mint (Monardella villosa ssp. franciscana), an endemic wildflower that is limited to California. Western monarchs love to feed off this native’s pollen, so keep an eye out for this butterfly species that is experiencing an unexpected resurgence, thanks in part to backyard gardeners who make a point to propagate natives. For upcoming wildflower hikes, check in with Friends of Edgewood (the next one is March 6, but it will be canceled if it rains heavily.)
Spectacular views of the hills and ocean are on display at this popular trail. And, lucky for us that early wildflower season coincides with whale migration and harbor seal births. Access is easy just south of Poplar Beach on Highway 1. The 3.7-mile trail (each way) begins with a pleasant walk that meanders through meadows and agricultural land before you hit the cliffs and turn south. The trail is mostly flat but can be muddy after rains. There’s a good opportunity to see hawks and pelicans as you search for native wildflowers. Seaside daisy (Erigeron glaucus) and common yarrow (Achillia millefolium) are always in bloom and mingle with invasive wild Brassicas. Mark your calendars for April 22, when the Coastal Wildflower Day Festival returns to Half Moon Bay State Beach a few miles down the road.
There are lots of trail options at this 3,000-acre preserve. For the most bang for your buck, start at the Ridge Trail where Page Mill Road and Highway 35 meet on the northwest corner. Take the trail to the top of Borel Hill and soak in the 360-degree views. Continue to the Ancient Oaks and Charquin trails for a full 5.7-mile loop. Varied topography allows for shade- and sun-loving wildflowers to grow under oaks and fallen trees and out in the open. All of the grassland trails, including the loop listed above, offer lots of wildflower-viewing possibilities. You might spot vibrant red Indian paintbrush (Castilleja affinis) or white Fernald’s Iris (Iris fernaldii) on sloping sunny hillsides. Look for western houndstongue (Cynoglossum grande), which is part of the borage family and thrives under the shade of oak trees.
Pulgas Ridge sits directly on the ridge of the San Andreas fault line, so it’s not surprising that there’s serpentine soil in these hills. The Bay Checkerspot butterfly’s primary habitat is the wildflowers that grow in serpentine soil. This species is unique to this part of the planet according to Dolkas, so you might very well spot one during a hike. This 366-acre dog-friendly preserve is adjacent to Edgewood making it convenient in case this parking lot is full or the trail is overcrowded. Take the Blue Oaks Trail to Hassler Loop. While you’re exploring the hills, look for magenta-hued Indian warrior (Pedicularis densiflora), a native perennial herb that blooms early in the season. It’s often found on slopes and attracts hummingbirds. Davy’s centaury (Zeltnera davyi) is a small pink native annual that blooms later in the season usually beginning in May.
Don’t let the looming hill intimidate you from making the hike to the top of Mori Point to spot coastal native wildflowers. Instead of starting at the Old Mori Point trailhead, mix things up and start your hike by walking the promenade that parallels Sharp Park Beach. When you reach the base of the bluff, go left to join Old Mori Trail to avoid the Bootlegger Steps that are a direct ascent. Follow the Coastal Trail switchbacks to the top of the bluff. Once you reach the crest, stop and soak in the view. There are several different bluff trails to follow, some that are precipitously close to the edge and some that zigzag up and over the ridge. These are the best trails to traverse in order to spot wildflowers. Look for creamy-yellow coastal tidy tips (Layia platyglossa) and vibrant yellow California goldfields (Lasthenia californica) that often grow together.