So let's break down this menu.
Orange halves with maraschino cherries: Washington is often associated with cherries, and while some "cherry tree chopping" story has been debunked as myth, he did apparently like to eat the fruit.
Chicken a la Maryland: I'm not really sure where they're going with this one, as Washington is well-known to have been very fond of fish, not chicken.
Southern Sweet Potatoes: I'd guess this is a nod to Washington's southern heritage.
Virginia Corn Bread: There was no such recipe, but there were recipes for plain old "Cornbread." Since Washington was born in Virginia and lived there at Mt. Vernon, I assume this is a convenient re-naming.
Cherry Salad: Again, the association of Washington with cherries. I found it interesting that this recipe actually specifies in the instructions that it is good for celebrating his birthday.
Boston Brown Bread: Boston is a place that is really steeped in American heritage. During the American Revolution, Washington forced the British out of Boston, which saved the city from an ongoing siege.
Chocolate Roll: Again, this seems like an odd choice. Why not Washington Cake?!?! I mean, really...It's an obvious choice...
Nuts, Raisins, Coffee: GW apparently loved nuts, especially hazelnuts and shellbacks (similar to pecans).
If you're extra curious, there's lots more information on what Washington and other Presidents liked to eat here!