Set on twenty-five acres adjacent to Rock Creek Park, Hillwood’s gardens feature a diverse and fascinating array of trees, shrubs and herbaceous plants, offering something to see in every season. 

Plants to note in the gardens:

• This year’s summer seasonal display is comprised of more than ten thousand warm season annuals and tropical plants. Flowers and bold foliage can be found throughout the grounds.  A highlight is the assortment of plants, overwintered in the greenhouse, which now fill the entrance to the museum in the porte cochere. Tiered planters of impatiens (Impatiens walleriana ‘Beacon Orange’), Rieger begonias (Begonia × hiemalis ‘Solenia Apricot’), and coleus (Plectranthus scutellarioides ‘Flamethrower Habanero') provide a pop of color among the greens.
• It is time for the rose garden to take the spotlight. The rambling rose ‘American Pillar’ is full of clusters of hot pink flowers. Considered singles, these have only one row of petals which clearly display bright yellow stamens in the center of the flower. This is an original plant from Marjorie Post’s tenure and only blooms once a year. Ramblers are often vigorous growers and ‘American Pillar’ demonstrates good disease resistance in our pesticide-free garden.
• There are still a few late-blooming azaleas putting on a show. Satsuki azaleas are the last to bloom in the gardens. Hybridized in Japan for at least five hundred years, they are thought to be a naturally occurring variety between two rhododendrons native to Japan. The Satsuki azaleas at Hillwood are low growing evergreen shrubs with a rounded form which become full of pink or white flowers. Their natural shape and habit along with their beautiful blooms have made Satsukis popular for bonsai.

Highlights in the greenhouse:

• There are still many orchids in flower in the greenhouses and the moth orchid collection (Phalaenopsis), in particular, is full of blooms. With a variety of colors and sizes, it is no wonder that these long blooming plants are so popular. Moth orchids like “low” light and can feel right at home in an east-facing window. They are relatively easy to grow because they enjoy temperatures typically found in our homes.
• There are many dancing lady orchids (Oncidium alliance) lighting up the orchid west house. Colmanara Catatante ‘Kilauea Karma’ is a beauty with long flower stalks full of burnt orange flowers. Looking carefully at the blooms will reveal a head, hands, bodice, and skirt set off by an extravagant costume piece giving this orchid its common name. Though a hybrid, its relatives are native to much of South America, Central America, Mexico, the West Indies, and even Florida.
• Zygopetalum Debby De Mello ‘Honolulu Baby’ is another orchid not to be missed. The flower is comprised of chocolate-colored petals and sepals which create a dark background for an electric purple lip edged in white. Zygopetalum can be grown outdoors for the summer where protected from direct sun. A fluctuation in day and night temperatures is crucial for flower bud formation. In nature, Zygopetalum are found in Brazil, Peru and Bolivia.