The Dahlia Society of California's free annual show runs August 15–16 at Golden Gate Park's Hall of Flowers, marking 100 years since the dahlia became San Francisco's official flower.

The Dahlia Society of California's annual Dahlia Show and Competition lands at the County Fair Building — the Hall of Flowers — in Golden Gate Park this Saturday and Sunday, August 15–16, with a milestone attached: 2026 marks exactly 100 years since the dahlia became San Francisco's official flower. Saturday hours are 10 a.m. to 5 p.m.; Sunday 10 a.m. to 4 p.m. Admission is free, all ages, no RSVP. The venue sits near 9th Avenue and Lincoln Way.

The city's Board of Supervisors designated the dahlia the official flower on October 4, 1926 — a bloom that had already been growing in Golden Gate Park since the 1880s, according to KQED. The Society, founded in 1917, now maintains more than 700 named varieties in the park's Dahlia Dell. The show brings more than 100 growers from across California — and sometimes beyond — competing for ribbons and cash prizes across categories that range from single blooms and triples to a Nature's Oddities class, a Junior division, and a photography competition. This year's floral arrangement theme is "San Francisco Icons," per the Society's official show page.

Jenna Kaiser, a dahlia ambassador with the Society, told KQED what to expect inside: "It's a room full of the most colorful, spectacular, perfect dahlias you've ever seen. A sea of blooms." The show also has a photo booth and a table hosted by local orchid growers.

The insider move: Go Saturday morning, when the judges are still circulating with clipboards and the blooms are at their freshest. Each entry is anonymous until ribbons go up, and watching the judges work is oddly compelling. By Sunday afternoon the winning blooms are all ribboned and the room gets crowded; Sunday is the better call if you want to see the results without the competition energy.

Getting there: Spots inside Golden Gate Park are limited to four hours and fill fast on weekends. Lincoln Avenue along the park's south edge, starting from 10th Avenue, offers unrestricted street parking — read the signs. Muni's N-Judah and 44 lines both serve the area. The back entrance off 10th Avenue and Lincoln is the exhibitor load-in zone and is not open to the public during the show.

If you only have two hours: arrive Saturday at 10 a.m., walk the single-bloom tables first, work your way to the arrangement section, and you're out before the lunch crowd arrives.