Initially I thought 青(あお blue/green) is used only for green traffic signal, but this can also be used for various things as well
Traffic Signal – 青信号
Nature and Plants – 青葉, 青芝, 青々
Food – 青りんご, 青野菜, 青ネギ
Unripe Things – 青梅
When a native speaker sees any object(let's say unknown object) with green color what word usually comes to their mind 青 / 緑?
by Immediate-Sort-6492