A graduate from Lincoln University with an honours degree in agricultural science, John Field-Dodgson won a Research Fellowship at the University of Natal in South Africa, where he got his PhD in plant science.
For many years, his work involved the use of traditional fertilisers, herbicides, sprays and other chemicals. He worked as a research manager for Wrightson's grain and seed division and bred Concord, one of the first proprietary rye grasses to be marketed in New Zealand.
While working in Australia he visited a farm that had switched to using biological farming methods.
''The farmer was working with New Zealander Graeme Sait, who is world-renowned for his biological and sustainable farming methods.
''At the time I thought it was interesting but didn't take a lot of notice. Gradually I realised that agriculture had relied on chemicals for too long and they were doing more harm than good.''
When Mr Field-Dodgson and wife Jan returned to New Zealand after the Victorian bushfires, they bought an olive grove near Amberley.
Mr Field-Dodgson carried on his agricultural and horticultural consultancy work, while Mrs Field-Dodgson set up a soap, lotion and cream business using their olive oil.
He discovered New Zealanders were embracing biological farming methods and a whole movement towards more sustainable farming practices was under way.
''There are three factors when it comes to soil - the physical factors, biological factors and chemical factors. For years we have concentrated on the chemical factors, while not taking into account the other two to a greater degree.''
All three needed to be in balance for a soil to be healthy and to produce healthy crops and, in turn, healthy animals, he said.
With increasing pressure placed on farming systems and the need to maximise as much plant growth as possible, the overuse of chemicals could also increase, Mr Field-Dodgson said. Biological farming used what was in the soil to improve it - microbes, fungi, protozoa earthworms and mycorrhiza.
It aimed to produce a balanced soil system which in turn produced healthier plants, but also helped fight against pests, diseases and weeds.
Biological activity, particularly with the mycorrhiza, could actually help unlock some of the nutrients that were locked up in the soil.
''If I can do one thing, it would be to get farmers and horticulturists to look at what is happening around them,'' Mr Field-Dodgson said.
''The way we farm must and will change, but it will only occur at grass-roots level with farmers and some help from local governments because of environmental pressure.''
- by Amanda Bowes