Kirklees Council has been accused of sending out mixed messages as allotment holders face big rent rises in the next three years.
Fees are set to rise by some 128 per cent as the council looks to bring rates in line with other local authorities.
The council has written letters of consultation to allotment holders.
It is proposed the new charges will be brought in from 2015.
Anne Dickinson, of the Batley and Birstall Civic Society, said the increase would discourage people from taking over vacant plots.
She said: “The council is encouraging people to grow their own vegetables, eat healthier and go out, but then turn around and say people are going to have to pay more.
“In the Longfield Road site in Heckmondwike, pensioners pay £10 for an allotment. If the cost goes up then they will probably just think to go to Aldi for their groceries.”
Last year, The Batley and Birstall Civic Society was awarded £6,500 from the Heritage Lottery Fund to promote the use of allotments in the district.
The group is writing a book called A Growing Affair which will chart the use of allotments and the people behind them from 1950 to 2013.
Members have also been producing a DVD, which they hope will encourage more people to take up the hobby.
Mrs Dickinson said: “Having an allotment helps you stay healthy and gets you out in the fresh air. It is best medicine in the world. It creates a lot friendships as well.
“We are finding more and more people are wanting to take up the vacant allotments and need to council to help allocate them.”
Kirklees has more than 1,800 plots on 100 sites.
A council spokesperson said: “We have written to allotment plot holders about a proposal to increase annual rates from 2015, to bring them in line with other local authorities.
“The cost of providing allotments with water, fencing, waste removal and general site maintenance has increased year on year.
“The new charges would enable the council to replace ageing systems and provide good quality, well maintained sites.
“Our allotments will still provide excellent value for money - If the proposals are accepted, by 2017, the cost of an average allotment plot will be just over one pound per week.”