Vic bushfire brought under control

A raging bushfire in Victoria's Dandenong Ranges is now under control.

The CFA issued a Watch and Act warning for the one hectare bushfire in Monbulk at after 4pm on Wednesday, warning residents two homes were at risk.

The fire started during a routine burn-off at a property on David Hill Road that quickly spread and destroyed a semi-trailer parked nearby.

"To have a fire of this type is very rare at this time of year," CFA operations officer Colin Brown told 3AW.

"Don't wait until the end of the year to clean-up your properties."

Roads surrounding the fire were blocked during the blaze but are expected to be reopened soon.