North Yorkshire Police said Ms Gardener was last seen at her home address in High Street, Scalby, yesterday, and are extremely concerned for her welfare.
Ms Gardener is described as 5ft 2ins tall, with long blond hair and fair skin.
She is believed to be wearing a black anorak-style coat and a hoodie.
Anyone with any information about Ms Gardener's whereabouts should call 101 or 999 for an immediate sighting.