Four fire engines and around 25 firefighters were called to a grass fire in Coombe Lane in Croydon.
Four hectares of grass and mixed woodland were damaged by fire.
Station Manager Bob Scrivener, who is at the scene, said: “Crews worked extremely hard on one of the hottest days of the year to bring the fire under control.
“During the hot weather we are attending a large number of grass fires across London.
“We’re asking the public to take care not to drop cigarettes or matches on dry grass and to keep a very close eye on barbecues. Dropped glass can also start fires as the sun can magnify the sun’s rays. Grass fires can quickly spread and cause serious damage, so if you see grass smouldering, please call 999 immediately.”
The Brigade was called at 1250 and the fire was under control at 1606. Fire crews from Croydon, Woodside and Addington fire stations attended the scene.