Ring Mountain Open Space Preserve

Ring Mountain Open Space preserve is one of the best things about living in San Francisco if you're a plant nerd. A short 20-30 minute drive across the Golden Gate Bridge and into southern Marin County and you're standing on a small hill surrounded by stunningly beautiful native flowers while enjoying postcard perfect views of San Francisco and Mt. Tamalpais.

San Francisco as seen from Ring Mountain in April

Once upon a time (ohh, say, the 1950s) the urban planners in the Bay Area were busily deciding how to manage the relentless growth the post-war economy brought to the region. One of those unrealized plans had a lovely 6 lane freeway perched along the ridgetop of the Tiburon Peninsula connecting to a new bridge to San Francisco via Angel Island and Alcatraz Island. Ring Mountain, located at the start of the peninsula, was slated to be topped/leveled and a regional shopping mall placed there, with convenient access to San Francisco provided by this wonderful new bridge and freeway.

Mt. Tamalpais as seen from Ring Mountain

Thankfully we had our freeway revolt and this plan never happened. Ring Mountain remained undeveloped and in the early 1970s a spectacular flower was discovered, a species of Calochortus, that would finally seal the deal for Ring Mountain to forever remain open space.

You may be noticing a theme in my blog posts. Serpentine. Ring Mountain is full of it, and in fact, the rarity of many of the flowers found on the mountain is due to the serpentine outcrops found there. Calochortus tiburonensis, Allium lacunosum var. lacunosum,  Monardella purpurea, and more are serpentine species. This lucky happenstance of plate tectonics gives Northern California its full and fascinating flower diversity. The mountain seems to have something interesting in flower from mid-March through June and into July. Let's check out some of the more interesting species and when they bloom:

Calochortus umbellatus, mid-March

Lasthenia californica, mid-March

Dodecatheon hendersonii, mid-March

Tauschia kelloggii, mid-march

Toxicscordion species, mid-March

Leptosiphon androsaceus, mid-April

Sidalcea malviflora var. laciniata, mid-April

Layia platyglossa, mid-April

Achillea millefolium, mid-April

Ranunculus californicus, mid-April

Sisyrinchium bellum, mid-April

Calochortus umbellatus, mid-April

Thermopsis californica, mid-April

Calochortus tiburonensis, late May

Allium lacunosum var. lacunosum, late May

Eriophyllum confertiflorum var. confertiflorum, late May

Hesperolinon congestum, late May

Castilleja rubicundula ssp. lithospermoides, late May

Delphinium hesperium ssp. hesperium, late May

Silene californica, late May

Triteleia peduncularis, late May

Monardella purpurea, mid-June

Clarkia rubicunda, mid-June

Dudleya cymosa, mid-June

Eriogonum luteolum var. caninum, mid-June

Hemizonia congesta ssp. lutescens, mid-June