Labour’s heavily criticised manifesto includes a short passage dedicated to a Land Value Tax, hidden on page 86 in a section entitled ‘Local Communities’.
The manifesto says a Labour government after the election will “initiate a review into reforming council tax and business rates and consider new options such as a land value tax”.
This would involve including the value of land while calculating council tax, which currently only uses the value of the property itself.
Jeremy Corbyn's 'garden tax' could cost families thousands of pounds every year
The Conservatives have warned this switch will unfairly target those with gardens, yards or large estates, increasing the average council tax by 224 per cent across England.
According to their own research into Jeremy Corbyn's proposal, the yearly tax bill for the average family home in England would increase from £1,185 to an eye-watering £3,837.
In some areas the increase could be even higher, such as Birmingham where it would increase by 320 per cent.
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Jeremy Corbyn during a visit to Hackney Marshes Football Pitches, to highlight Labour's manifesto commitment to ensure 5% of the Premier League's television rights income is diverted to the grassroots game, during a General Election campaign
A report by Oxfordshire County Council, made up of Labour, Lib Dems and Greens, admitted those with gardens would be hit hardest.
The report said: “Normally, the winners are those plots that have little or no garden and the losers are those where houses stand in large grounds and where maximum development is permitted by the planning regime.”
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And Westminster’s all-party group on gardening and horticulture also warned against the policy.
Labour's manifesto vowed to investigate reforming council tax
Conservative MP Rebecca Pow said: “Looking at this at face value, I would urge caution with any policy which might deter people from wanting gardens.
"It is well documented that taking part in gardening activities and having access to green space are hugely beneficial to health and well being.
It is right that those who have worked hard to achieve a home with a garden are not then penalised for it
"I would also be concerned that this kind of a policy would target rural areas far more than urban areas, putting an additional strain on peoples pockets, accentuating the urban/rural divide.
"It is right that those who have worked hard to achieve a home with a garden are not then penalised for it and are treated fairly."
The new policy could see tax for the average family home increase by 224 per cent
The National Farmers Union and the Institute for Public Policy Research think tank were also among the groups to hit out at the proposal.
A Labour spokesman dismissed the claims as "desperate nonsense from the Tories". The manifesto contains no details about how the tax would be applied.