In conjunction with The Garden Show, on Saturday, June 21st PICA presents Sea of Green: A Short History of the Lawn, a humorous and insightful look at the evolution of the lawn by cultural historian David Ritchie. “In general gardening lore,” says Ritchie, “Lawns are like Victorian children — they sometimes appear in the pictures, but one doesn’t talk about them unless it’s absolutely necessary.” The lecture takes place at 4 p.m. at the exhibition site. Admission is free and the public is invited.