People reported Sunday that McGinley, 47, who plays Dr. Perry Cox on the Emmy-nominated TV show, woke up Saturday morning -- the same day he was to present an award at the Creative Arts Emmys -- and took yoga teacher Nicole Kessler down to their garden, using flower ideas as a ruse.
McGinley told the magazine, "I told her, 'Sit down here to see the view of the ocean' -- we live in a bird sanctuary -- and I said, 'Will you marry me?' and I took out the rock."
The 34-year-old Kessler, who met McGinley on the beach through his 9-year-old son, Max, said yes.
The ring was a 2-carat round diamond flanked by two 1-carat diamonds and a couple of smaller baguettes, People said.
"I wanted it to be a big rock in the middle, which is Nicole because she is the rock in this relationship. And then on either side, I put a carat, and that represents me and my son, Max," the romantic McGinley said, adding that the other stones represent the kids to come.