Frances Hodgson Burnett’s 1909 novel was half wishful thinking, half unforced feeling as it celebrated the persistence of the past and the power of one garden to literally heal the sick. In this 1991 musical adaptation Lucy Simon’s score has enough uplift to float a dozen dirigibles, but they’re anchored by the raw heartache of Marsha Norman’s book. Porchlight’s production, directed by L. Walter Stearns, is fluid and deeply felt, and the singing soars. The cast is unimprovable, though Mallory Baysek and Drew Mikusha stand out as the troubled children who are healed. Through 5/28: Fri-Sat 7:45 PM, Sun 3 PM, Sat 5/6-5/27, 3 and 7:45 PM, Theatre Building Chicago, 1225 W. Belmont, 773-327-5252, $28-$30.