Mr. Green Jeans earned his moniker from his distinctive apparel, a pair of farmer's overalls (later, jeans and a denim jacket) in his signature green. He was a talented and inquisitive handyman who provided assistance at the Treasure House. He frequently visited the Captain with the latest addition to his menagerie of zoo animals.

Mr. Green Jeans was the subject of an urban legend that claimed he was the father of the late musician Frank Zappa. The confusion probably arose from the title of song by Zappa, "Son of Mr. Green Genes", from Zappa's 1969 album, Hot Rats. Zappa was, in fact, the son of Francis Vincent Zappa, Sr. The rumor has also been attached to shock rocker Alice Cooper and heavy metal pioneer Ted Nugent.