"Salad days" is a Shakespearean idiomatic expression to refer to a youthful time, accompanied by the inexperience, enthusiasm, idealism, innocence, or indiscretion that one associates with a young person. More modern use, especially in the United States, refers to a heyday, a period when somebody was at the peak of their abilities—not necessarily in that person's youth.
...My salad days, / When I was green in judgment, cold in blood...
The phrase became popular only from the middle of the 19th century, coming to mean “a period of youthful inexperience or indiscretion." The metaphor comes from Cleopatra's use of the word 'green' — presumably meaning someone youthful, inexperienced, or immature. Her references to "green in judgment" and "cold in blood" both suggest qualities of salads. 
Fowler's Dictionary of Modern English Usage summarizes several other possible meanings of the metaphor:
Whether the point is that youth, like salad, is raw, or that salad is highly flavoured and youth loves high flavours, or that innocent herbs are youth's food as milk is babes' and meat is men's, few of those who use the phrase could perhaps tell us; if so, it is fitter for parrots' than for human speech.
Queen Elizabeth II during her Silver Jubilee Loyal Address, referring to her vow to God and her people when she made her 21st birthday broadcast: "Although that vow was made in my salad days, when I was green in judgement, I do not regret nor retract one word of it."
The phrase has been used as the title of several books, including the novels Salad Days by Francoise Sagan and by Charles Romalotti, the autobiography The Salad Days by Douglas Fairbanks Jr., and numerous cookbooks.
Paul Greenberg, "Tuna's End," New York Times Magazine article: "Aboard one Zodiac, Frank Hewetson, a 20-year Greenpeace veteran who in his salad days as a protester scaled the first BP deepwater oil rigs off Scotland, tried to direct his pilot toward the net so that he could throw a daisy chain of sandbags over its floating edge and allow the bluefin to escape."
In film, television, and theatre
In the 1987 Joel and Ethan Coen film Raising Arizona, Nicolas Cage as H.I. “Hi” McDunnough uses the expression twice in the first few minutes of the film. Speaking as the background voiceover rather than as a character, he first says, “These were the happy days, the salad days as they say, and Ed felt that having a critter was the next logical step. It was all she thought about." A few moments later, again as the voiceover, he says, "Our love for each other was stronger than ever, but I preminisced [sic] no return of the salad days."
Episode 33 of the television series Monty Python's Flying Circus is called "Salad Days".
Independence Day 1996) "Are the salad days over for President Whitmore?"
The idiom is used again in the opening line of the track "Lovers Who Uncover" by the Little Ones: "Where do all the lovers meet with one another, in an effort to uncover what has happened to their salad days?"
The phrase is also used in the track "Spotlight (Oh Nostalgia)" from Patrick Stump's Truant Wave EP: "Oh, nostalgia I don't need you anymore. 'Cause the salad days are over and the meat is at my door."
Frank Zappa's song "Electric Aunt Jemima" contains the phrase as well: "Holiday and salad days, and days of moldy mayonnaise".
Talib Kweli's song "Friends & Family" on his album Gutter Rainbows uses the phrase in reference to his early career: "Rhyming in Greenwich Village circa 1993. Yeah those were the salad days, my career's appetizer."
Talib Kweli's song "Ms. Hill" on his album Right About Now uses the phrase, saying, "We used to kick it in the salad days, but she look at me like she don't know me when she see me nowadays."
"Salad Days" is a song by the Cardiff post-punk band Young Marble Giants. The lyrics are "Think of salad days, they were folly and fun, they were good, they were young".
The phrase is also used in the chorus of the track "Vince The Loveable Stoner" from The Fratellis's Costello Music album: "And I haven't seen a pupil in his eyes for 16 days, the catholic girls love him in a hundred million different ways, and he's been up for days, in a thick malaise, he's only listened to the salad days."
Adrian Belew's 1999 album, Salad Days, consists of acoustic recordings of solo work as well as song from his King Crimson era.
The song "What Would Jimi Do?", on bassist Tony Levin's album Resonator begins with the lyric "Lately, I've been thinking back, back into my salad days"
- Jack, Albert (2005). Red herrings and white elephants: the origins of the phrases we use everyday. HarperCollins. p. 44. ISBN 978-0-06-084337-3. Retrieved 2011-04-28.
The phrase is a simple one with a simple origin provided, once again, by Shakespeare. In 1606 the Bard wrote the play Antony And Cleopatra, which includes the line: 'They were my salad days, when I was green in judgement.'
- Michael Macrone (1990), "Salad Days", Brush up your Shakespeare!, pp. 126–127, ISBN 978-0-517-18935-1
- Walker, John Louis (2002). Shakespeare and the classical tradition: an annotated bibliography, 1961-1991. New York: Routledge. p. 340. ISBN 0-8240-6697-9. Retrieved May 3, 2011.
- Fowler, H. W. A Dictionary of Modern English Usage. Oxford University Press, 1926.
- Sagan, Francoise, Salad Days, Dutton Adult, 1984, ISBN 0-525-24238-4
- Romalotti, Charles, Salad Days, Layman Press, 2000, ISBN
- Fairbanks, Douglas, Jr., Salad Days, Doubleday, 1988, ISBN 978-0-385-17404-6
- Desaulnier, Marcel, Salad Days: Main Course Salads for a First Class Meal, Simon & Schuster, 1998, ISBN 978-0-684-82261-7
- Powell, Pam, Salad Days: Recipes for Delicious Organic Salads and Dressings for Every Season, Voyageur Press, 2011, ISBN 0-7603-4043-9
- Paul Greenberg (June 21, 2010). "Tuna's End". New York Times. Retrieved 2010-06-24.
- Video on YouTube
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