The roof is on fire nelly.
Onion roof is on fire.
I wonder how much selection had to be done or if welsh onion seeds from any nursery would be fine.
Nevertheless onion domes are popularly believed to symbolise burning candles.
In 1917 noted religious philosopher prince yevgeny trubetskoy argued that the onion shape of russian church domes may not be explained rationally.
These are allium fistulosum the welsh onion.