In the summer I like to visit demonstration gardens to see how well the plants and vegetables performed in this area. Demonstration gardens are a great way to learn what works in the Washington DC metro area and how to manage our local issues, such as deer and rabbits. Each county that has a Master Gardener program usually has at least one demonstration garden, managed by the volunteer Master Gardeners. These are open to the public and free. To find such a garden, call your local county Master Gardener program representative (your local extension agent). Some have several to showcase various environmental conditions and some use the garden as a place to teach or host workshops.
In Northern Virginia, the Master Gardeners of Northern Virginia (Arlington and Alexandria) now have eight demonstration gardens. They recently added Buddie Ford Nature Center Garden. The Prince William County Master Gardeners manage a very large Teaching Garden at St. Benedict Monastery, 9535 Linton Hall Road, Bristow. Within this property are mini gardens to illustrate certain conditions or issues, such as a deer resistant garden, shade garden, vegetable garden, and pollinator garden. The Loudoun County Master Gardeners uses Ida Lee Park on Ida Lee Park Drive, Leesburg, as a teaching garden.
In Maryland, the Montgomery County Master Gardeners manage six demonstration gardens. The Prince Georges County Master Gardeners have demonstration gardens at their headquarters at 6707 Groveton Drive, Clinton.
Some plant societies such as the National Capital Dahlia Society have demonstration gardens specific to their plant of interest. Contact the society directly to see if they have one. The National Capital Dahlia Society has the Nordahl Exhibition Garden for displaying dahlias at the Agricultural History Park in Derwood, MD. Plant NoVA Natives has a list of demonstration gardens that feature native plants on their site.
If you know of any that I have not listed here, please contact me and let me know.