A sharp increase in outdoor gatherings combined with very dry weather have contributed to more serious blazes caused by barbecues and outdoor heaters, the fire service has said.
Norfolk Fire and Rescue's safety lead warned of how quickly small fire pits and patio heaters can become serious problems, especially when precautions are not taken.
It comes after a fire pit caused a blaze which spread across gardens and damaged four Norwich homes on Saturday evening.
Greg Preston, the fire service's head of community safety, said: "We've seen a rise in incidents cause by fire pits and patio heaters, which can be a risk if not used properly."
As gatherings with other households are still only permitted outdoors under lockdown rules, many people have turned to such methods of keeping people warm while socialising in gardens.
But Mr Preston said recent dry weather and a lack of understanding of safe use means "fires can go from something small to something very serious, very quickly".
He added: "The different way in which we're socialising at the moment is going to be more of a risk. People are outside more and because it's dry but not very warm people are using these things.
"Our message would be for people to take care and think about the consequences of using them and how quickly fires can spread, especially now with the undergrowth being so dry. We're heading into a time of heightened fire risk around the county."
People are being urged to read instructions thoroughly before operating patio heaters and fire pits, while also making sure everyone involved knows how to use them safely.
Advice can also be found on the Norfolk County Council website.
Mr Preston said: "We're already starting to see situations where these fire pits are setting light to hedges, fencing and sheds. And these incidents can quite easily spread into a house as well – that's not uncommon.
"I would urge people to take the time to read those before use and think about where they're placing their heater. Don't place it too close to undergrowth and make sure everything is clear around it.
"It's very easy to underestimate how quickly undergrowth adjacent to something like that can catch fire."
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