Potting soil causing increasing number of house fires

Potting soil planters are causing a surprising new trend of accidental fires in homes, according to John Coull, manager of the Mississauga office of Origin and Cause Inc.
Coull was speaking at an A.S.A.P Education Series event, Fire Loss Claims Handling – Investigation to Litigation, just outside Toronto on May 26.
Potting soil does not have the same components as soil found it the ground – it is 85% peat moss and 15% other product – making it combustible.
A fire in a planter can happen for a number of reasons, most often because someone has placed smoker’s materials in the potting soil.
However, there are instances where the potting soil self-ignites, Coull said. “I have had several fires, and it usually happens from about now to early August; the potting soil left unattended or untended will catch fire.”
The potting soil if it’s watered will look like soil. However, if it’s not watered, it starts to look like dust. The plant dies, the potting soil dries out and sitting there in the direct sunlight starts to absorb the heat. Potting soil by its very nature is supposed to absorb water, but when there’s none of that, it absorbs the heat.
“These fires all start by breaking out through the base of the planters,” Coull said. “They are absorbing heat, they are retaining heat and eventually they break down. There is an issue with moisture content and lack of moisture content that is being researched now.”
Coull was called to a home in Bowmanville in April when the owner looked out the window and saw smoke coming from her deck. When she went outside, there was a fire in two potting soil pots sitting on her deck. By the time she went to get water to douse them, the fire had spread to the cedar trees and then to her vinyl-clad house.
“She lost her whole house all because of potting soil,” Coull said.