Or, "moon June swoon."

A disparaging adjective used to describe work by poets and lyricists who lack the creative energy or ability to move beyond the most obvious and simple rhymes.

Example:

He possesses a bent for sheer melodicism, and the kind of quick, lyrical gift that make the "moon-June-swoon" school of songwriters look like teeny-tiny babies.
(Source: www.metroactive.com review of Billy Bragg's album William Bloke)

The expression is derived from the relative ease with which one could create a simple love song using easily rhymed "-oon" words, of which there are several that fit tired romantic cliches.