When I was a little girl, I misheard “a riotous bloom” as “a riot in bloom.”
Today, on my commute to work, the peonies were the very definition of a rebellious riot in bloom: tossing their gorgeous, heavy, fragrant frowsy heads, careless of how their skirts fell or whose eye they arrested: loud and crowded and dangerous on the hillside.
I could almost hear their throaty, wispy voices crying: “We’re here! Mid-June! Get used to it!”
I could almost see the placards held in their glossy, leafy fingers that they’d thrown together the night before in a drunken fit of spontaneity, with blowsy strokes of their petals in vivid pollen: “Beauty is fleeting, but give it a chance!”
Haddayr Copley-Woods 
Beautiful description of a glorious event!
Um…. I am 39 and I am only learning right this second that “a riot in bloom” is not a thing. Granted, I have always wondered about it. And “a riotous bloom” does make more sense…. huh. You learn something every day. Even at my wizened age.
Thanks, Heather! And Kelly — my little sister WHO IS EVEN OLDER THAN YOU IF YOU CAN IMAGINE ANYONE THAT OLD — has _also_ just learned it is ‘a riotous bloom.’ I am educating the public!