Angela Rowe, 39, had been convicted after a trial at Kingston Crown Court last month which heard she helped run a regime where the atmosphere was more like an army camp than a nursing home.
Her colleague, Lorraine Field, 42, was jailed for 15 months for mistreating residents and Desmond Tully, 33, was fined pounds 750 for one count of mistreating a resident.
The police investigation into the scandal was launched in 1994 after The Independent revealed that a secret Buckinghamshire County Council report had found residents were subjected "to a catalogue of abuse, deprivation, humiliation and torment."
Residents at Stoke Place Mansion House and Stoke Green House in Stoke Poges, Buckinghamshire, were slapped, had their hair pulled and jugs of water thrown over them.
Residents were denied toilet paper, soap and toothpaste and one woman with Down's Syndrome was made to eat her meals outside, even in the pouring rain.
Rowe ran the homes from 1983 to 1993 with her husband, Gordon, who died in his fume-filled car in March last year on the eve of charges being pressed against him by police.
He would have faced charges of rape and would have been held "principally responsible" for the cruelty at the homes, which were run under the name of Longcare Ltd.
An inquiry by Buckinghamshire County Council in 1994 unearthed the catalogue of sexual and physical abuse by Mr Rowe at the homes, which housed about 70 residents.
Sentencing the trio at Kingston Crown Court yesterday, Judge John Baker said: "The primary aim of those who take on responsibility for looking after those who are mentally handicapped must be to see as far as possible that the residents lead a happy and contented life as far as they can within their limitations.
"Physical contact must be limited to helping a resident or restraining him or her when necessary. Physical punishment and any form of humiliation or degradation can't be allowed."
He told Rowe the offences she had committed were "extremely serious matters". She sat emotionless in the dock as Judge Baker passed the 30-month sentence. Lorraine Field was sentenced to 15 months.
Judge Baker added: "Parliament has said that the maximum sentence for ill-treatment is two years' imprisonment or a fine, or both.
"There is an urgent need for Parliament to provide a comprehensive review of the courts' sentencing powers."
Nevertheless, relatives of the victims said they were delighted to see Rowe and Field put behind bars.
Terry McCarthy whose son Shaun, 37, was abused by Rowe, said: "We would all have wanted more but it was good to see them going to prison."
The families of the victims are now looking to pursue civil action claims against Rowe.Reuse content