Frost is seen on the ground in Ingersoll, Ont., in this photo from November 2012. (Betty Price / MyNews)

Environment Canada has issued a frost advisory for the Region of Waterloo and Wellington County.

The advisory includes Kitchener, Cambridge, Guelph, Erin, Mount Forest and Arthur.

Temperatures are expected to drop to near or below the freezing mark.

The weather agency says some plants may be damaged or destroyed by the frost. People should cover up any frost-sensitive plants or trees.