I just saw some clips of Gion Kobu’s Hassaku and noticed that geiko Haruchizu had on a red nagajuban and not the commonly seen light pink that geikos tend to wear. Any reason for this? I normally see maikos wearing red.

Sometimes newer geiko opt to wear red juban instead of pink to show that they're still growing (it can also depend on what juban are available if the girl comes from a large okiya) ^^