Green’s Dictionary of Slang

a term of affectionate/familiar address, usu. to an atttractive woman.

1865		Prairie Chicken 1 June 3/2: What is the propriety of calling a pretty girl [...] ‘peaches,’ etc.? [DA].
1949		S.J. Perelman letter 19 May in Crowther Don’t Tread on Me (1987) 96: Well, Peaches, it was a jim dandy.
1952		W.R. Burnett Vanity Row 270: The blond check-room girl with the blue eyelids looked up at him indifferently, then [...] ran her eyes over him. Wesson went over to her. ‘Hello, Peaches’.
1971		T.C. Bambara Gorilla, My Love (1972) 19: Watcha mean, Peaches?