Spring Flowers in DC

U.S. National Arboretum
http://www.usna.usda.gov/Gardens/collections/collections.html
It is hidden just off Route 50 (New York Avenue) into town for motorists taking the Baltimore-Washington Parkway
446 acres of fabulous flora and fauna, especially azalea and Asian collections, a virtual inner city park, are fascinating

National Capitol Columns stood at the east portico of the United States Capitol Building from 1829 to 1958
50-acre Brookside Gardens in Wheaton Regional Park, Silver Spring, MD
full of colorful flowers in bloom and a wonderful green house installed with interesting art works in shapes of animals. “The artfully landscaped grounds, woods, formal gardens, aquatic gardens, a Japanese Tea House and conservatories displaying flowering plants and exhibits that change with the seasons.”

http://www.mc-mncppc.org/parks/facilities/wheaton_regional.shtm