Historical clue formulations

• Field of flowers — 2019-02-09
• Field with lots of growth? — 2018-11-04
• Gray matter? — 2016-03-27
• Plant expert's field — 2009-09-01
• Field of flowers? — 2005-07-25
• Horticulturist's topic — 1998-03-12
• Science class — 1996-04-18