At choir practice last night, a few members asked me about what to wear at Mass this coming weekend. I don’t like advising people on fashion, but as you might suspect, the question of color came up. Again.
I hope I didn’t come off as too dismissive, but I offered, red, orange, yellow–all colors of flames. (I didn’t think of the green flames of boron or copper sulfate.)
My predecessors often urged alignment with the festivities, not just red for Pentecost. Last Saturday the observance for Our Lady of Guam was blended into Ascension, so floral and Pacific wear was suggested from the singers.
One of my honored predecessors was a concert singer in her secular career, and so advocated black skirts and trousers plus white tops for Big Events like Triduum and Christmas. These days I tell people to wear the best of their best for Easter Vigil and Midnight Mass.
What do you think? Why have we become mostly fixated on red for the seventh Sunday after Easter, and not other days? Red is the least-used of the liturgical Final Four, so is that a factor? Sit in the purple chair and decide for your real or imagined parish: if your choir isn’t robed, would you want them color-coordinated?
Catholic Sensibility 
I am a firm believer in not wearing colors to match vestment colors.
I am not a vestment.
I am not wearing a vestment.
I am not part of the decor.
While I don’t mind at all if other people freely choose to wear colors associated with the vestment colors of the day, I think rather dimly of people being asked (or worse, told) to do so by parish staff or some such (parents can decide what their family members may wear and be grateful if said members comply). It’s not as bad as hectoring/badgering the PIPs to hold hands at the Our Father (and waiting until they comply before proceeding with it), but it’s an old busybody impulse finding its way under a new guise/rationalization.
White, of course, has even older associations with Pentecost.
And, in the Eastern Churches, green is the associated color.
So, wear a Mexican, Italian or Hungarian flag.