Try the Mystery Plant contest. This site shows how to integrate native plants, habitat, and pest management into your long-term plans for your yard. It includes lists of native plants, lists of native plant nurseries in the whole Chesapeake Bay region, and other links. He lists butterflies with the first and last sighting for several years. Other lists include nectar host plants with the butterflies and moths they have attracted, and the reverse, butterflies and moths with the nectar plants they prefer in his garden.
Site also has links and sources.
Of the five sections of this site, one is a journal including the creation of a new backyard wildlife habitat in northern Virginia. The Cherry Blossom Page from the National Park Service has all the information you need about the trees and the festival. This URL has remained the same for several years. And best of all, this ezine is written for the Washington, D.C., metropolitan area. A calendar of events and the gardening guidance are appropriate for the mid-Atlantic area.