Visitors enter through a bougainvillea-laden arbor, and can order tapas and wine during the set.
A $10 cover charge pays for the musicians; there is no minimum purchase.
The concerts are presented by Laguna Beach Live!; co-founder Lucinda Prewitt said they help satisfy a need in town.
"We don't have a lot of music in Laguna," she said. "It's a hassle to go up to the Orange County Performing Arts Center, or to Fullerton to listen to jazz."
She received two thank-you notes after the July 11 concert; one writer said they hadn't heard jazz of that caliber in Laguna since they went to the White House in the 1970s.
"Our mission is to provide top-quality music that's accessible," Prewitt said, in venues that would show off Laguna.
There's room for 130 people in the Rose Garden, and the July 11 show boasted 129 attendees.
One-third of those are Laguna regulars, Prewitt figures; the remainder either live in the area or are visiting tourists.
Concert-goers often save a seat before the show, then wander down to the nearby beach until it starts.
The event, which receives funding from the city through the hotel bed tax, began with a focus on classical and chamber music.
Following discussions with musicians and teachers like Bijon Wilson and Eric Dries, the group opted to expand to the jazz shows in early 2005.
Claes Anderson, owner of the Hotel Laguna, offered to host the shows at his venue.
Anderson also provides rooms and venues for artists during the organization's annual music festival, which will reach its sixth year in January.
"The biggest thing that we really focus on is the music festival," Prewitt said. She sees it as a way for people to discover contemporary classical music in an inexpensive and non-intimidating way.
The next Jazz @ the Beach concert will be from 6 to 8 p.m. Wednesday, with the Latin Jazz Syndicate.
For more information, call (949) 715-9713 or visit www.lagunabeachlive.org.