Morrison does not regard this record as a true album, as Bert Berns compiled and released it without his consent. A few months previously, Morrison signed a contract that surrendered virtually all control of the material he would record with Bang Records. The songs were recorded in March 1967 and had been intended to be released on four separate singles. The album jacket became notorious as a model of bad taste. It featured a strange swirl of circling brown vines (and drug connotation) surrounding a sweaty looking Morrison. Greil Marcus described it as a "monstrously offensive, super psychedelic far out out-of-sight exploding" design. Morrison's then-wife, Janet Planet, said "He never has been, never will be anything approaching a psychedelic user - wants nothing to do with it, wants nothing to do with any drug of any kind". As the singer recalls, "I got a call saying it was an album coming out and this is the cover. And I saw the cover and I almost threw up, you know." Later, after Berns' death, Morrison would express his displeasure on a couple of "nonsense songs" he included on the contractual obligation recording session. One was entitled "Blow In Your Nose," and another was titled "Nose in Your Blow."
Of the eight songs on the album, all were composed by Morrison except "Goodbye Baby (Baby Goodbye)" and the last song, "Midnight Special". Clinton Heylin contends that the first side of the album "makes for one of the great single-sided albums in rock", whereas Greil Marcus, the album's most hostile critic, found it "painfully boring, made up of three sweet minutes of 'Brown Eyed Girl' and... the sprawling, sensation-dulling 'T.B. Sheets'". "He Ain't Give You None" is an urban tale of "lust, jealousy and sexual disgust." It references Notting Hill Gate and Curzon Street in London, England, places Morrison would have been familiar with when he lived there during his earlier touring days. It contains the words, "You can leave now if you don't like what is happening." Brian Hinton compares "the delighted contempt of the singer, the song's graveyard pace, the stately organ and stinging guitar" to the Highway 61 period of Bob Dylan.
Allmusic gave the album a 3-star rating and wrote that "Although Van Morrison's first solo album is remembered for containing the immortal pop hit "Brown Eyed Girl," Blowin' Your Mind! is actually a dry run for his masterpiece, Astral Weeks."Entertainment Weekly gave it a B-rating, noting that it "displays the pitfalls of late-'60s blues rock: meandering solos, hippie sentiments, and the occasional fuzz-tone guitar. But in the hand of Van the Man, those vices are virtues, and what could have been tedious is often hypnotic."