There have been rumblings about this for decades, and progress has been achieved in some places. But, especially in South Auckland, valuable fields have been lost forever. During the past 10 years alone, 200 growers around Auckland have sold up because of rezoning and subdivisions.
Rich, deep soil is precious. It grows fresh vegetables and lush grass. Its value will only rise as such land becomes scarcer.
Environment Minister David Parker and Agriculture Minister Damien O'Connor last week released a draft national policy statement proposing requirements on councils when they decide whether land should be used for agriculture or urban development.
''We need to house our people and to feed them too,'' Mr Parker said.
The idea is that development on ''highly productive'' land not be allowed unless to meet shortages. Under such circumstances, long-term cost-benefit analysis would need to be prepared and alternatives to any development considered.
While this is a balancing act and another potential obstacle in the way of meeting desperate housing needs, too much fertile land is going under.
As Horticulture New Zealand has said, this country needs to be able to grow all the fresh and healthy food it requires, in a world where it will be difficult to import fresh food because of climate change.
One study showed that between 1990 and 2008, a third of new urban areas had spread on to this most valuable land.
And a 2013 study showed 175,000 lifestyle blocks covered 870,000ha in 2011. A sizeable proportion of this is ''highly productive''.
There is also the issue of reverse sensitivity. It is possible - with good planning and buffer strips - for horticulture and houses to co-exist. More commonly, however, the noise, smells and sprays of active agriculture prompts complaints from adjacent residents.
Many thousands of hectares of the best land has gone in Auckland, Waikato and Canterbury. But parts of the Taieri have also been lost.
Mayor Dave Cull has said this should not have occurred. He welcomed the intent of the new approach, which was consistent with the council's second generation district plan (2GP).
Two pressures encourage development on the best soils. They tend to be flat or close to flat and such land is generally much easier and cheaper for building infrastructure and houses. It is also difficult to make money from vegetable growing, at least on a smaller scale. It is often back-breaking work, and the power and system of supermarket buying discourages multiple and regional sources of produce.
The very best soils should have received better protection long ago. There must be a place for potatoes and not just property.
