Penngrove is a census-designated place (CDP) in Sonoma County, California, United States, situated between the cities of Petaluma and Cotati, at the foot of the western flank of Sonoma Mountain. It is part of the North Bay subregion of the San Francisco Bay Area. The population was 2,637 at the 2020 census. it was formerly a freight station on the Northwestern Pacific Railroad and a center of egg and chicken farming.
Geography
Penngrove's downtown consists of Main Street, a street linking Old Redwood Highway to Adobe Road. Penngrove School is located at the corner of Adobe Road, where Main Street becomes Petaluma Hill Road.
Lichau Creek flows southward through the town, paralleling the railway. The creek feeds into the Petaluma River, which flows to San Pablo Bay.
Due to the Sonoma Mountain's ancient volcanism, Penngrove is rich with obsidian and petrified wood. Its soil is unique, composed mainly of clay-like adobe, which has been used for centuries as building material. A prime example of adobe architecture is the Rancho Petaluma Adobe, a State Historic Park in nearby Petaluma.
Penngrove enjoys a mild Mediterranean climate.
According to the United States Census Bureau, the CDP covers an area of , all land.
Demographics
Penngrove first appeared as a census designated place in the 2010 U.S. census.
The age distribution was 18.9% under the age of 18, 6.0% aged 18 to 24, 20.7% aged 25 to 44, 29.8% aged 45 to 64, and 24.6% who were 65 years of age or older. The median age was 49.2 years. For every 100 females, there were 98.0 males, and for every 100 females age 18 and over there were 92.7 males age 18 and over.
There were 1,063 households, of which 25.2% had children under the age of 18. Of all households, 47.5% were married-couple households, 7.3% were cohabiting couple households, 25.9% had a female householder with no spouse or partner present, and 19.3% had a male householder with no spouse or partner present. About 28.8% of all households were made up of individuals, and 13.8% had someone living alone who was 65 years of age or older. The average household size was 2.47. There were 652 families (61.3% of all households).
! Race !! Number !! Percent
|-
| White || 1,994 || 75.6%
|-
| Black or African American || 22 || 0.8%
|-
| American Indian and Alaska Native || 38 || 1.4%
|-
| Asian || 62 || 2.4%
|-
| Native Hawaiian and Other Pacific Islander || 12 || 0.5%
|-
| Some other race || 224 || 8.5%
|-
| Two or more races || 285 || 10.8%
|-
| Hispanic or Latino (of any race) || 442 || 16.8%
|}
History
The Mexican government granted Rancho Cotate to Captain Juan Castaneda in July 1844 for his military services in the region. The grant encompassed present-day Penngrove, Cotati and Rohnert Park. Cotate Rancho is a part of Vallejo Township which encompasses the plain between Sonoma Mountain and Petaluma Creek, San Pablo Bay, with an east–west line dividing the tract from Santa Rosa Township."
In October 1870, the San Francisco and North Pacific Railroad completed the first railroad from Petaluma to Santa Rosa, running through Penngrove.
Education
It is in the Petaluma City Elementary School District<!--ELM 30230--> and the Petaluma Joint Union High School District<!--SEC 30250-->.
Name
The naming of Penngrove is uncertain; there are three main "histories" of the name's origin. thumb|Photograph taken looking northwest along the railroad tracks in Penngrove, next to the former train station and hotel|alt=Early photograph of the original "Penn Grove" railroad station in downtown Penngrove
Ruth Anderson, the famous "Bell-Lady" of Penngrove (who lived on the site of the old schoolhouse on Oak Street), recalls,
"In the late 1860s, two brothers by the name of Penn came out from Pennsylvania and bought of land in this area. They planted the area with olive trees, but when the trees matured it was found that the olives were not edible. The Penn brothers tore out many of the groves, sold the land and moved away. However, while they were here, they named their place Penn's Grove. Later it was changed to "Penn Grove," and still later, because our mail got confused with that of Pine Grove (the former name of Sebastopol), the U.S. Postoffice Department changed the name to one word—Penngrove." (Harris 1980)
Other accounts state that because there was another town with the name of Penn's Grove in New Jersey, this could be a reason as to why the post office changed the name. Others claim that the Woodward family, who came from Pennsylvania, named their property Penn's Grove in honor of their home state.