More than 400 people have signed a petition in an attempt to save allotments in Isleworth said to be a haven for rare birds and other wildlife.
The Duke of Northumberland's estate wants to build homes on Park Road allotments, across the road from Syon Park .
The estate, which owns the park and the neighbouring allotments, has already told gardeners they will have to leave and offered them an alternative site within the park.
But the Isleworth Society has now asked Hounslow Council to list the allotments as an 'asset of community value' - an application backed up by a petition with more than 400 signatures.
The protected status, if approved, would mean any owner looking to sell the land would have to allow the local community six months in which to put together a bid.
However, as Northumberland Estates, which manages the duke's business interests, is looking to develop the land itself it says the protected status would not affect its plans.
A spokesman for the estate said it planned to build a mix of different sized homes on the allotments site for private rent.
The proposals are due to go on display this Saturday, November 7, at the Northumberland Room in Syon House, from 10am to 2pm.
One allotment holder, who asked not to be named, said: "If we have to move we have to move but it would be a tremendous loss to the local area. We're vehemently against them building on this land.
"There's so much wildlife here, including a lot of endangered birds. We have cuckoos and lesser spotted woodpeckers to name just a couple of the rare species."
She acknowledged the landowner had been "as fair as they could be" but said the alternative site near Lion Gate in the north of the park was less accessible.
A spokesman for the estate said it had been consulting with allotment holders for about seven months and 24 out of the 34 current tenants had signed new agreements for the estate to maintain their allotments at a different site.
"This (the proposed housing) is about contributing to the long-term viability of the house and grounds which is a considerable local asset," he said.
"It would deliver some flexible housing provision for the local area and would be done very sensitively."
He would not give any further details of the proposed scheme, including the number of homes planned, ahead of the public exhibition this weekend.
Christine Diwell, of the Isleworth Society, said she understood the council had rented the land from the duke for 100 years but its lease had expired last year and was not renewed.
"It's one of the few remaining bits of the old market garden fields, and we feel it should remain as open land," she said.