梦溪石《千秋》Thousand Autumns, Chapter 95 [Vocabulary]

黄花菜 huánghuā cài (noun) day lily

1) citron daylily (Hemerocallis citrina Baroni)

2) golden needles (edible flower)

There is a colloquial saying which is 黄花菜也都凉了 huánghuā cài yě dōu liángle which means “It’s too late to do anything” but literally means that the day lilies are cold.