In Candyland we have rules. Rules of etiquette, that is. We don’t care which fork you use to eat your salad; but speaking of greens, the story goes like this: Once upon a time, a woman found herself feeling a bit blue, sitting at a restaurant waiting on a friend. In walked her dinner date with a totally unexpected and totally uncalled-for bunch of daisies. Walking home that night, the woman decided her rule: Anytime you receive flowers (welcome ones, that is), your mission is to?within the next week or so?send flowers to someone else.Think chain letter, but sans threats of death, poverty, boils, bankruptcy or locusts. Just cuz. It makes the concrete jungle a more colorful place. In support of this rule, Spruce, the charming West Village florist is, for the next two weeks, offering DailyCandy subscribers 10 percent off any floral arrangement.