What does the cryptic crossword clue "The besetting sin of the Greens? (4)" mean?

The definition is "The besetting sin of the Greens?". The wordplay uses a cryptic definition. Cryptic definition The answer is ENVY.

The besetting sin of the Greens? (4)

Guardian Cryptic #29004 | 20 Across | 2023-02-27 flower