sow one's wild oats
Definitionsow some wild oats / plant (some) wild oats , to indulge in promiscuous sexual activity, to sow or scatter one's seed, especially while still young.
(1) King Jaffe (James Earl Jones) about Prince Hakim (Eddie Murphy) in Coming to America (1988): ' Hakim came to America to sow his wild oats.'
(2) Brad Allen/Rex Stetson (Rock Hudson) and Jan Morrow (Doris Day) in Pillow Talk (1959):
-- Brad: ' So I have sown a few wild oats.'
-- Jan: ' A few!? You could qualify for a farm loan.'
(3) Rosalie Maggio. Dictionary of Bias-Free Usage (1991): ' Both young men and young women do this while their parents pray for crop failure.'