"Mellow Yellow," in tandem with its predecessor "Sunshine Superman," established Donovan as the ultimate bearer of good vibes at the dawn of the psychedelic era. Countercultural bliss, of course, did not prohibit commercial success, and "Mellow Yellow" was a very big hit, reaching number two in the U.S. (and the Top Ten in Britain). The big hook in "Mellow Yellow" is not a riff or note, but a jazzy walking beat which carries the instrumental intro until Donovan's usual breathy vocal makes its entrance. The verses are certainly mighty melodic in a pop folk-rock fashion, with the singer's sly declarations of love for various fantastic women accompanied by only minimal electric guitar and bass. What makes this a psychedelic folk-rocker, rather than a sassy jazz tune, is the insistent chorus in which Donovan gleefully announces that they call him Mellow Yellow. Only in 1966 and 1967, perhaps, would that nickname be worn as a badge of honor, but it fit in well with the psychedelic era, when the more outrageous the language and flouting of convention, the better. It was certainly difficult not to sing along with that chorus, too, particularly as it was immediately rejoined by a responsive knowing, nudge-nudge affirmative whisper. (Though those whispers have sometimes been rumored to have been voiced by Donovan's friend Paul McCartney, actually these were by Donovan.) After a near drum-roll of a turnaround, the song glides into an instrumental break of celebratory partying, with voices whooping it up as a striptease-like brass section takes over the main riff. That partying atmosphere, something like a bridge between the Beatles' "Yellow Submarine" and "All You Need Is Love" ambience, sticks with the rest of the song, particularly the fadeout. The famous lyrical reference to an electric banana gave rise to fantastic rumors that smoking banana peels would get you high, though the words were surely intended in a lighthearted humorous fashion, not as a serious revelation. A little-known cool cover version of "Mellow Yellow" was done by the jazz-soul combo Young Holt Unlimited.