Tickets are on sale for the 50th Annual Festival of Houses and Gardens, March 20-April 19 in historic Charleston, S.C. Each daily event costs $30. Last year’s festival sold out, so reservations are advised. Information: (803) 722-3405. . . . Pulitzer Prize-winning author William Styron will give a free reading at 8:30 p.m. Saturday at the Lodge at Koele resort on the Hawaiian island of Lanai. Information: (808) 949-4131. . . . The San Francisco Museum of Modern Art is now open on Mondays and closed Wednesdays; previously, it was the reverse. Information: (415) 357-4000.