The roof is on fire nelly.
Onion roof is on fire.
Fistulosum as it can tolerate dry soil and it stores water in its tissues so it helps avoid loosing the house during forest fires.
These are allium fistulosum the welsh onion.
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.