A £1m lottery bid will be submitted to transform Rivington’s terraced gardens.
But experts have warned that even this contribution from Heritage Lottery Funds would not be enough for a full restoration of the site near Chorley.
Community charity Groundwork said that the ongoing cost of employing a warden and maintenance would be too high.
And it has ruled out rebuilding the pagoda in the Japanese gardens, built in the early 1900s as part of Lord Leverhulme’s estate.
Now the charity is setting up a community forum and asking for ideas from local people about what they would like to achieve.
Suggestions include opening up the Dovecote Tower, known locally as the Pigeon Tower, clearing overgrown footpaths, cleaning the Japanese lake and reinstating some of the stonework on the site.
Lucy West, development officer at Wigan-based Groundwork which is acting as an agent in the bid process, said: “We’re looking at a partial restoration of the whole terraced gardens, some of which is inaccessible.
“Paths are overgrown and people are not confident about using the area because they feel isolated.
“We would look at clearing ponds and vegetation, introducing new plants and repointing some of the stonework if possible.”
She said that they were liaising with Rivington Heritage Trust and the landowners, United Utilities, about the restoration.
Ecologists would also be consulted to ensure that appropriate planting was introduced.
She said: “It really is hard to put a figure on how much would be needed but maybe as much as a million.”
Bids to the Heritage Lottery Fund have to meet strict criteria, including wide-ranging consultation with the public.
Groundwork is already in the process of setting up a community forum and is hoping this will be achieved in the next two months.
About 30 people turned up to the first public meeting in Rivington and more are scheduled this month.
Lucy said: “We have about eight people who are interested in being on the forum so far but really would like more people to come forward.”
“The Community Forum will be an independent group, which will report to the Rivington Heritage Trust Board providing advice concerning community and user group involvement with the terraced gardens.
“It will also play an active role in the decision-making regarding the management and any future work on the gardens.”
A spokesman for United Utilities said: “We are very keen to see these historic gardens conserved and protected for the enjoyment of future generations and are actively involved in Rivington Heritage Trust’s plans to prepare a Heritage Lottery bid.
The next public consultations will be from 4pm and 7pm on Tuesday, March 27, at Horwich Library, Jones Street, Horwich.
And the second on Wednesday, March 28 at Rivington Church parish hall, Horrobin Lane, Rivington.