In later poetic works Fletcher returned to more traditional forms. These include The Black Rock (1928), Selected Poems (1938), for which he won the Pulitzer Prize in 1939, and The Burning Mountain (1946).
In the late 1920s and 1930s he was active with a group of 11 other Southern writers and poets known as the Southern Agrarians. This group published the classic Agrarian manifesto I'll Take My Stand, a collection of essays rejecting Modernism and Industrialism.
In 1937 he wrote his autobiography, Life is My Song.
In 1947 Fletcher published Arkansas, a beautifully written history of his home state.
Fletcher suffered from depression and on 20 May 1950 committed suicide by drowning in a pond near his home in Little Rock, Arkansas. Fletcher is buried at historic Mount Holly Cemetery in Little Rock.