Wild purple-blue violets (native and introduced).
Though this isn’t the peak season for Viola adunca ssp. adunca (western dog violet) to bloom, this native plant can be found flowering in the coastal grasslands on Point Reyes at most times of the year. Another Marin population grows in Potrero Meadow flowering in April on Mt. Tamalpais, near the picnic area restroom.
Two other purple-blue non-native violets can be confused with our native. One is the fragrant European weed, sweet violet, Viola odorata. This species can be found flowering now in Samuel P. Taylor State Park, growing under the streamside coast redwood trees. Plants occur with either white or purple flowers. They thrive in a cool habitat with fog-drip in other places too, such as by the Lucas Valley Road redwoods just west of the Big Rock. In gardens, which were their origin in the USA, they need watering in the summer.
The other weedy blue violet in Marin has no fragrance. This is European dog violet, Viola riviniana. It may be a nuisance in some Marin coastal gardens. Erroneously it sometimes is called V. labradorica.
Photos by Doreen Smith.
Viola adunca ssp. adunca – (western dog violet)
Viola odorata – (European sweet violet)
Viola riviniana – (European dog violet)