National Mall; free
The 13 gardens that are scattered around the Smithsonian museums along the Mall are an officially accredited museum in their own right — and one that many people visit without even realizing it. At the Enid A. Haupt Garden, just south of the Smithsonian Castle, you’ll find all sorts of alien-looking tropical plants, including the chenille plant, which currently appears to be growing a mane of pink feather boas. Nearby, on the north side of the Arts and Industries Building, is the Kathrine Dulin Folger Rose Garden (above), which is blooming with robust, disease-resistant roses that you’ll want for your own garden, including pale purple Poseidons and Yellow Submarines. Take a walk to the east side of the National Museum of Natural History and meander through the Smithsonian’s Pollinator Garden, where towering tangles of coneflowers and lavender attract a slow parade of bees and butterflies.
Franciscan Monastery of the Holy Land in America
1400 Quincy St. NE; daily, 9 a.m.-4:45 p.m., free.
If you can’t make a pilgrimage to Jerusalem or Rome, consider traveling to Brookland instead. The Northeast D.C. neighborhood is home to the Franciscan Monastery of the Holy Land in America, and the monastery’s steep, hillside garden is scattered with replicas of religious sites you’d have to travel the world to see. Under a veil of vines bearing orange flowers, you’ll find a full-size copy of Jesus’ tomb and other Roman catacombs. Additional opportunities for prayer and contemplation abound in the monastery’s front-yard garden, which showcases tropical plants reminiscent of the Middle East, including palm trees and angel’s trumpet shrubs. That’s also where you’ll find the monastery’s famous rose bushes, which peak in spring. While there aren’t as many blooms In August, you’re likely to have the landscape all to yourself, your thoughts accompanied by a shimmering choir of cicadas.
31st and R streets NW; daily except Mondays, 2-6 p.m., $10.
In the 1920s, pre-eminent landscape designer Beatrix Farrand sculpted a peaceful idyll of terraced lawns, winding pathways and flower-speckled meadows on this Georgetown estate. These green spaces have been kept up to Ferrand’s strict specifications, and they draw legions of landscape architects as well as casual admirers. Both kinds of visitors glide down graceful staircases to discover a series of outdoor “rooms” that go from formal to wild the further you get from the mansion at the top of the garden — the former home of a wealthy Washington couple, now a Harvard research library and museum. Farrand had benches custom-built to fit the landscape and instructed future gardeners as to the types of plants that look best together, but for all of its carefully constructed beauty, Dumbarton Oaks isn’t a showy garden. You won’t find a lot of flowers here in August, but it’s a perfect place to take a contemplative walk or read under a shady tree. (If it’s flowers you’re looking for, come back in September for a spectacular chrysanthemum display.)
1644 31st St. NW; Tuesdays-Saturdays, 10 a.m.-4 p.m., Sundays, noon-4 p.m., $3.
If you could chat with the boxwood hedges at Tudor Place, they’d catch you up on about 200 years of D.C. gossip. Rumored to have been grown from a clipping from Mount Vernon, these precision-trimmed shrubs stand at the front entryway of the former home of Martha Washington’s granddaughter, Martha Parke Custis Peter, and her husband, Thomas Peter, the son of Georgetown’s first mayor. Committed upcyclers, the Peters loved repurposing old materials in their gardens — including a pair of hat racks from the old Treasury Building, now used as planters. Summer is a great time to admire the yellow coneflowers and purple garden phlox, which are growing so exuberantly that they threaten to encroach on the garden pathways. Keep an eye out for cottontail rabbits as you admire the bowling green — an expansive lawn guarded by two sleek greyhound statues — or watch birds frolic in the multi-tiered fountain on the green’s southern end.
4155 Linnean Ave. NW; Tuesdays-Saturdays, 10 a.m.-5 p.m., $18 suggested donation.
In the 1950s, heiress Marjorie Merriweather Post built her Northwest D.C. estate with two goals in mind: She wanted it to eventually serve as a museum for her art collection, and she wanted space for throwing fabulous parties — in the house, but also in the surrounding gardens. The French garden, off of the home’s French drawing room, is ideal for intimate conversations, while the Lunar Lawn was built for massive garden parties. If you’re more interested in admiring flowers than hobnobbing, visit the cutting garden, where you can get lost among unruly thickets of zinnias, amaranth and marigolds. Or escape the heat in the Japanese-style garden, where you can take shelter under a maple tree or walk across paving stones that dapple the pond and tip your hat to Cecilia, Hillwood’s resident turtle. Thirsty for fall colors? Come back in September for a blaze of autumn foliage and matching borders of bushy mums.