Fifth-generation farmer Deborah Corrigan's property is surrounded by housing developments on three sides, but she is determined her farm will not go the same way.

"They're desperate for the land, they're knocking, they're ringing, they're doing everything to try and speak to us but we're holding them all at bay because we're not interested," she said.

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Her farm at Clyde is on the outskirts of Melbourne's south-east, where housing developments are fast overtaking farmland.

A new report from the University of Melbourne has warned if that trend continues the city's food production will be at risk.

Researcher Rachel Carey said Melbourne's fringe produces around half the vegetables grown in Victoria and it needed to be protected.

"We have a rapidly growing city, we're going to need at least 60 per cent more food by 2050," she said.

A billboard advertising one of the new developments at Clyde. ( ABC News: Jess Davis )

"We have a lot more pressures on food supply, from climate change as well as a growing population, so if we're able to keep these areas of fresh food production on the city fringe then that's a buffer against these kinds of risks to our food supply."

The report found the State Government was not doing enough to protect Melbourne's agricultural land, and it was falling behind other cities.

"The regulation isn't strong enough and what's happened is we haven't held the line as we should have done," Dr Carey said.

"We've allowed the expansion of the urban growth boundary to occur into that farmland."

Stay or go?

Farmers are divided over whether to stay and fight the developers or cash in and move else where.

Chris Schreur is moving his Clyde farm 100 kilometres down the road to Gippsland.

Chris Schreurs said farming on the city fringe has become too difficult. ( ABC News: Jess Davis )

He said he was happy to be moving because farming in an urban area had become too difficult.

"To move from one farm to another on a tractor now takes from 20 minutes to half an hour, so logistically it's a bit of a nightmare for us," he said.

"There's always a little bit of sadness, leaving something that the family's built their business upon, but the reality is for us to move forward and to be competitive on a domestic stage as well as an export stage we need to embrace change."

Long-term plans

It's not just Melbourne grappling with this problem. Dr Carey said all the major state capitals were facing the same pressures.

"They're all growing rapidly, they all have areas of farming on their fringes that are important for producing food," she said.

Half of Victoria's vegetables are grown around Melbourne's fringes. ( ABC News: Jess Davis )

The Foodprint Melbourne report looked at Vancouver and Toronto in Canada, which have introduced 50 year plans to protect farming on the fringes.

"They're giving certainty — certainty to farmers, planners as well and it allows farmers and goverment to invest," Dr Carey said.

"We also found what these cities are doing is going beyond protecting. They're introducing a suite of measure to promote farming on the fringe to ensure those farmers can say."

A new food bowl

But Mr Schreurs said it was too late to protect his tract of land.

"I think that policy should have been made 40, 50 years ago, had a bit more foresight and said 'well this is the land allocated for horticulture or agriculture' and made it a bit more spacious," he said.

Workers clean leeks at a packing shed in Melbourne's south-east. ( ABC News: Jess Davis )

But he hoped it was possible to create a new food bowl further out of the city.

"I think It's very important for us to have a food bowl in Australia, we've got a great history of agriculture in this country and we want to continue."

The ABC sought a response from Victoria's planning and agriculture ministers but they declined to comment.