Historical clue formulations

• National flower of Mexico — 2026-06-07
• Showy flower native to Central America — 2025-04-08
• "The Black ___" (1987 crime fiction best seller) — 2024-05-01
• National flower of Mexico — 2023-08-06
• Flower cultivated by the Aztecs — 2022-12-04
• Popular paper flower variety — 2022-11-11
• Mexico's national flower — 2022-10-11
• Mexico's national flower — 2020-03-14
• Flower named for a Swedish botanist — 2017-02-26
• Mexican bloom — 2016-05-12
• Mexico's national flower — 2015-05-26
• Colorful perennial — 2012-11-18
• "The Black ___" (2006 film) — 2011-05-11
• Mexican bloom — 2010-12-29
• Mexico's national flower — 2010-07-28
• Flower once cultivated for food — 2010-03-14
• National flower of Mexico — 2008-07-20
• National flower of Mexico — 2006-06-25
• Pale violet — 2005-02-25
• Veronica Lake film "The Blue ___" — 2004-09-14
• Showy bloom — 1999-10-04
• Showy flower — 1996-07-21
• Cactus___ — 1996-06-14
• Black_____ (sensational 1947 murder case) — 1994-07-21
• Flower named for a Swedish botanist — 1993-11-25