Timing the Cherry blossoms is very tricky so don't be surprised if you don't actually see them. The date varies every year and depends on the weather. We went in March 2018 when they were initially predicting an early bloom, but about a week before our trip some cold spells came through and slowed them down and they didn't end up peaking until first week in April. Also hotels will be more expensive during that time. But Spring is a beautiful time to go and you will see something blooming if not the Cherry blossoms. We ended up seeing very few buds around the Tidal basin but the tulip magnolias by the Smithsonian Castle were in bloom and beautiful.
You can follow this site (
https://cherryblossomwatch.com/) to get an idea of when they will peak. But if you need plane tickets and hotel, it will be hard to time it exactly.