The National Arboretum, host to 446 acres of gardens and historical monuments, will keep its doors open later every Saturday during the next two months, with the exception of July 3. The Arboretum, open daily from 8 a.m. to 5 p.m., is welcoming garden enthusiasts to enjoy its space until 7 p.m. on Saturdays.

The 40-minute tram ride that highlights the main features of the Arboretum will still be in operation on Saturday evenings and may serve as a good introduction for the newcomer. There will be one and sometimes two special twilight tours every Saturday. The tours will be free of charge and guided by on-site experts beginning at 5 p.m. Some of the tours include a late-blooming azalea tour June 5, a Prairie Meadow tour July 17 and a crape myrtle tour July 31.

More information is available on the Arboretum’s Web site, www.usna.usda.gov.

 — Virginia Russell