Zimmerman, who is now in his 12th season with the Nationals, said he wanted to give back to the D.C. community and supply local kids with a field nicer than any he played on growing up.
"I've been playing here for a long time, meeting a lot of people in the community -- whether it's at the park or just being around, going out to dinner," the first baseman said before the dedication ceremony. "To give them something to play on as nice as this was special to me."
In addition to Zimmerman, Saturday's ceremony also featured Washington D.C. Mayor Muriel Bowser, Ward 6 councilmember Charles Allen and Nationals principal owner Mark Lerner.
Nationals manager Dusty Baker was also in attendance, and he and Zimmerman posed for photos with several dozen Little League teams that had gathered for the occasion.
After all the teams got their pictures taken, Bowser, Lerner, Zimmerman and others spoke at a brief ceremony.
"We're really honored, right in the heart of Ward 6, to name this field in your honor," Bowser said to the first baseman.
Zimmerman and Bowser participated in a ceremonial ribbon-cutting, then Zimmerman threw the ceremonial first pitch to a Little League catcher.
Zimmerman credited former Nationals manager Matt Williams with inspiring him to become involved with the Nationals Dream Foundation, which partnered with Under Armour and the Cal Ripken Sr. Foundation to construct the new field.
Speaking at the dedication ceremony, Zimmerman told the kids in attendance he hoped they'd use the field to play baseball, soccer, football or anything else.
"Whatever you guys want to do on this field, that's what it's for," Zimmerman said. "You don't have to play baseball, you can do whatever you want, just go out and have fun. Be active and learn to be good teammates."