Greta Gerwig comes of age with ‘Lady Bird’

NEW YORK » Greta Gerwig has been an actress in 25 films, a co-writer on five and co-director of one. She’s assembled wardrobes, done makeup and — thanks to her 5 foot-9-inch height — held the boom mic. She has, in a sense, been building up for a long time to her directorial debut: “Lady Bird.”

“I was accumulating my 10,000 hours,” Gerwig said in a recent interview in a tucked-away room at Lincoln Center. “When I finished this script, I thought: You’re still going to learn things but you’re not going to learn anything more by not doing it. Whatever learning happens now is going to happen by doing it. I just decided to take the leap.”

It’s at this moment while contemplating the culmination of her professional life that a famished Gerwig first spies her lunch. “Oh my goodness it’s a sammy,” she exclaims — a revelation quickly followed by another. “Oh my feet are so dirty from standing outside barefoot.”

For Gerwig, it comes naturally that the most earnest inner ambitions can appear, from the outside, a little funny, too.

Gerwig’s “Lady Bird,” which opened Friday in New York and Los Angeles, is a loosely autobiographical coming-ofage story about a high-schooler named Christine with the self-proclaimed nickname “Lady Bird” (Saoirse Ronan) who aspires beyond her middle-class Sacramento life. From Roman Catholic school, she dreams of New York or at least “Connecticut or New Hampshire, where writers live in the woods.”

The film — richly detailed, shrewdly observed, altogether a beauty — has already found some of the best reviews of the year, placing it among the early awards-season favorites. It boasts numerous revelations — including the performances by Ronan and her fictional mother, Laurie Metcalf — but none more so than this one: Gerwig is an exceptional, fully formed filmmaker, right out of the gate.

“She nailed it in the way that she did because she’s incredibly open to people