Rhododendron Sunday/Mother’s Day at Shore Acres State Park – May 12, 2024. Treat mom and family to a delightful day at Shore Acres south of Charleston, Oregon. In the garden, Park Rangers will have a display of cut blooms and will be available to answer your questions about rhodies. The park is open from 8 a.m. to dusk and the Garden House will be open from 11 a.m. - 3 p.m. with refreshments provided by the Friends of Shore Acres.