FEATURE
Growing challenges Adapting for climate change
Gerard Hutching looks at the potential impact of climate change on the arable and horticultural industries and asks what can be done to ensure the future remains bright.
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r Brent Clothier, Principal Scientist at Plant & Food Research, is reluctant to be viewed as a Pollyanna when it comes to climate change, but he cannot fail to see a rosy side to a climate-warming scenario for horticulture (extreme events notwithstanding). “There’s massive potential in areas that aren’t traditional horticultural areas, such as Taranaki. At present in New Zealand there are about 180,000 hectares under horticulture and arable farming. However, in terms of climate resources, there are around 2 million hectares that could potentially sustain these industries,” he says. That said, there are significant value-chain issues that need to be overcome before Taranaki becomes another fruit bowl. Clothier’s Plant & Food Research colleague Dr Jill Stanley echoes the positive sentiments. “I’m an optimist. I think New Zealand will do well as long as it plans well, including adaptations for more intense weather events. We have a huge opportunity to grow a wide range of crops successfully,” she says. Plant & Food Research is just one of the growing body of organisations, including government departments, regional councils, research institutes and businesses, which are mapping out a path for the future as the planet continues to warm. Industry body Horticulture New Zealand predicted in 2019 that by 2028 the land area in horticulture would have risen to 140,000 ha, with most export fruit growth expected in avocados, pipfruit and kiwifruit, while the
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greatest vegetable-growing expansion would be in potatoes, onions and process vegetables. Victoria University climate researcher Professor James Renwick says climate change means more energy in the atmosphere, feeding into weather features. When there is fine weather under a big high-pressure system, everything dries out faster, it is hotter, and droughts occur more quickly. On the other hand, when there is a storm there is more water in the air, and more rain falls. For vulnerable crops this could spell disaster, not that apples, cherries and lettuces have never been beset by damaging hail and downpours – just that these events will become more frequent and destructive. Some of the mitigation measures that researchers are investigating include: covered cropping and precision irrigation, developing new varieties which will perform under hotter temperatures, changing the type of crop grown, and shifting the locations of crops. Others are more transformational as a way of protecting the $10 billion of value that horticulture and arable farming represent for Aotearoa. In August 2019, the Government launched its draft National Policy Statement on Highly Productive Land, to ensure the country’s best growing land is not lost to lifestyle blocks and housing subdivisions. “Every year we put 40,000 ha under lifestyle blocks, asphalt and infrastructure. The result is ride-on mowers and ponies instead of productive land,” Clothier says. One cause for optimism: horticulture and arable farming have relatively modest carbon footprints. Nevertheless, companies such as T&G Global and
