Green is associated with St. Patrick, not red.
Green.
The original color was blue.
Green is most associated with St. Patrick's Day.
Green
red
It was originally blue, but over the years people started wearing green instead.
Green, which is the colour associated with Ireland. St. Patrick is Ireland's patron saint and St. Patrick's Day is Ireland's national holiday.
Originally it was blue.
Green and gold
Color blue was largely associated with this day in the early days of its celebration, color green has come to be associated with St. Patrick’s Day over the last many centuries.
No, even though the traditional color associated with St. Patrick's Day is green, it is not mandatory to wear green or to celebrate St. Patrick's Day. It would have to be assumed that if someone wears red or some other color on St. Patrick's Day, that is purely a fashion related choice about what that person feels like wearing or thinks will look good (or possibly, it could be related to the remaining supply of clean clothing) rather than being some kind of rejection of St. Patrick's Day.
When he was about 60 years old, St. Patrick travelled to Ireland to spread the Christian word. Green is associated with Saint Patrick's Day because it is the color of spring, Ireland, and the shamrock