You know it’s summer in San Francisco when the Stern Grove Festival launches, and this year’s premiere event is absolutely delicious: High rollers can get in on the festival’s annual fundraiser, The Big Picnic, a seated party with catered lunch that helps pay for the season of free concerts. Or, stroll over a bit later with your own picnic to lap up the sun and a performance by psychedelic soul songstress Janelle Monáe, with opener Midtown Social.