One of the most exciting times of the year in Washington DC is when the Cherry Blossoms reach peak bloom. Depending on many factors, peak bloom usually happens around early April. Tourists come from far way with the hope that they planned their vacation at the right time for peak bloom. For those who don't know, the Cherry Blossom trees were given to Washington DC by Japan more than 100 years ago. The most spectacular location to see the trees in bloom is around the Tidal Basin, near the Jefferson Memorial.
As for my photography, I prefer to shoot around sunrise. This means getting there really early but it also allows you to miss a majority of the crowds. Usually, by 9am the tidal basin is packed with people when the trees are in bloom.