Lee DeWyze Is Engaged!

Lee DeWyze, the 2010 winner of American Idol, has some more great news to celebrate.

The singer, 25, is engaged to model/actress Jonna Walsh, he tells PEOPLE exclusively.

“I’m excited,” says DeWyze, who popped the question July 16 over champagne on a private yacht under a fireworks-filled sky at Disney World in Orlando. The couple are planning to wed in the fall of 2012.

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“Jonna is a Disney freak,” he says. “They were playing love songs on the boat and I got down on my knee and asked her. I had a speech prepared but it all went out the window so I just asked her. She started crying and I said, ‘Is that a yes?'”

Indeed it was. DeWyze met Walsh last October while shooting a video for his single “Sweet Serendipity.” “We were casting and I saw her and said, ‘Let’s go with her.’ I thought she was cute.”

“We hung out and we went to a Lakers game on our first date. She’s a Lakers fan and I’m a Chicago Bulls fan and we just clicked out of the gate.” As for Walsh supporting another team, “We’re seeing a counselor about that,” he joked.

But DeWyze did seek another sort of counseling two months earlier: He consulted Walsh’s sister before choosing an engagement ring.

“We do all kinds of stuff together,” the singer says of life in Southern California with his fiancée. “We go to plays and exhibits and Jonna is really into the planning for the wedding.”

Though they have been dating for only eight months, DeWyze had no hesitation before popping the question. “When you know, you know,” he says. “We both feel that way. We don’t need to be together 20 years before we figure it out.”