Green’s Dictionary of Slang

okra n.

(US) the penis.

1992

(con. 1920–57) Randolph & Legman Ozark Folksongs and Folklore II 787: Other common names for the male organ are [...] okra [etc.].

In compounds

okra and prunes (n.) [coined by Gore Vidal (b.1925) for his novel Duluth (1983)]

(US) the male genitals.

1983		G. Vidal Duluth (1998) 62: Once a girl has dined, as it were, on a sparerib with yams, the very sight of okra and prunes is nauseous.
2002		Richy C. Richy’s Random Ramblings 🌐 okra and prunes.