Residents at Woodside House Care Home in Mauchline, Ayrshire, had unexplained bruises, were left with dirty and unkempt fingernails and hair, and had clothing that was dirty and stained with food.
The Care Inspectorate, Scotland's social care regulator, has served a formal improvement notice on the home, which houses up to 17 residents, giving it six weeks to improve. East Ayrshire Council has temporarily closed it to new admissions.
Inspectors visited in April, and found residents lacked even the stimulation of a television with the volume turned up. Residents became "distressed and agitated", due to a lack of activities, or because staff were unavailable for simple tasks like helping someone with dementia find their room.
Although some relatives praised staff, others said they did not have enough time to do their jobs. Care workers had to prepare evening meals and do laundry, which left them unable to help residents with mobility problems move around or go to the toilet.
The report says staff were inadequately trained including in handling of medicine, which was inappropriately stored. In one case, medication was found on the floor.
The home was rated inadequate on 12 separate measures relating to every area of care covered by the unannounced inspection.
A spokesman for the Care Inspectorate said: "Our inspectors found areas of significant concern. The quality of care was not acceptable. Our priority is always the safety and wellbeing of residents, so this improvement notice sets out what we expect the care home to do to ensure that the care provided improves. "We will be inspecting this service again soon to ensure progress is being made, and will continue to work closely with the home.
A spokeswoman for East Ayrshire Council said the home had been closed to new admissions. She added: "Ongoing intensive monitoring by council officers and Care Inspectorate officers has been in place and will continue, to ensure that action is being taken by the Care Home provider to make the necessary improvements."
Muhammed and Shamsa Arshad, directors of Hamilton-based Meadow Healthcare Ltd, which owns the home, were not available for comment.