The rise of the organic kiwi
Kiwifruit is a huge export crop for New Zealand farmers, and organic growers like Leo and Diane Whittle are leading the entire industry in raising the environmental "bar" and moving all growers closer to organic

By Laura Sayre

Under the Canopy: Organic kiwifruit hanging heavy although fertility is an ongoing challenge. Leo and Diane Whittle try to replicate the kiwi's native soil and other growing conditions for heathlier, naturally resistant vines.

Posted April 1, 2003: Every stop on the tour of Leo and Diane Whittle’s organic kiwifruit orchard is enjoyable, but the last is the most spectacular: that’s when Leo takes you up the steep hill at the back of the property to a narrow plateau where you can turn and look northeast to the Pacific Ocean.

In the distance you can see White Island out in the Bay of Plenty, with its active volcano sending up puffs of smoke. In the foreground you can see the neat squares of the Whittles’ and neighboring farms, the neatly trellised blocks of kiwifruit vines framed by tall, dense shelterbelts of Japanese cedar (Cryptomeria japonica).

In between, scattered across the landscape, you can see a dozen or more cold storage facilities—vast, immaculate metal warehouses surrounded by mountains of the wooden crates in which kiwifruit are shipped around the world. Eighty percent of New Zealand kiwifruit production—a total of 60 million trays a year, at 3.5 kilograms a tray—is centered around the town of Te Puke (pronounced t’ POO ky), just off to our right, and from here you can believe it.

". . . the whole industry is moving ever closer to organic . . . growers across the spectrum have been rethinking production methods, with IPM (integrated pest management) strategies, for instance, now nearly universal."

The Whittles have been producing kiwifruit here since 1987, and began transitioning to organic ten years later, receiving full certification from Bio-Gro, New Zealand’s leading organic certification group, in 2000. Their farm is “what’s called a Darby & Joan operation,” as Leo puts it: four ‘canopy’ hectares of kiwifruit vines, 7.4 ha altogether (about 10 acres of vines on a farm of 18 acres)—small enough to be managed by a husband and wife team. Apart from harvest, which requires a crew of ten for three or four days in May, Leo, age 60, and Diane, 58, do all the work themselves.

It is a second career for both of them: trained in horticulture, the Whittles went abroad in their late twenties, kicking around for five years before settling down on Vancouver Island, Canada. Leo turned to forestry, taking logging contracts and managing a crew while Diane raised their two children. They stayed for ten years. But they missed the New Zealand climate and the lifestyle that goes with it, and Leo had always wanted to try growing kiwifruit. “When the kids reached the end of primary school, we knew it was now or never,” he reflects. After a year’s trial period, they bought this property with its established orchards, clearing the least productive area to build a house.

Emerging strong from a late-80s slump in the market

The early years weren’t easy. Twelve years ago a hurricane ripped through the neighborhood, lifting the roof off the water tank and dropping it in the middle of one of the canopy blocks. They’ve also had an earthquake (the house stood), and a heavy dusting of volcanic ash from Mount Ruapehu, 200 km (125 mi) to the south (luckily this came just after harvest, not before).

More serious was the stagnation of the kiwifruit industry in the late ‘80s, a reaction to rapid expansion in the 1970s and to the removal of agricultural subsidies in 1984. But the Whittles’ perseverance has paid off: when they bought in sixteen years ago, established kiwi orchards were selling for around NZ$100,000/canopy hectare; now they’re NZ$250,000/canopy hectare (a leap from about US$126,000/ac to US$315,000/ac).

Fruit prices recovered after the industry was reorganized in the early 1990s, so that instead of multiple kiwifruit exporters operating independently, one company known as Zespri acts as a single seller in the global marketplace. “Some people refer to it as a monopoly,” Leo explains, “but technically it’s a ‘monopsony’—they have sole right of purchase. Eventually we realized that as kiwi growers in New Zealand, we shouldn’t be competing against each other. In reality, we’re competing against kiwi producers in other countries, and beyond that against other fruits—and beyond that against other foods people choose to eat.” Zespri promotes kiwifruit consumption worldwide, oversees strict quality control programs among its producers, and works to develop new markets, as with the recently introduced Kiwi Gold—a sweeter, smoother, yellow-fleshed variety that already accounts for one-sixth of NZ kiwifruit exports.

"The biggest challenge for the organic kiwi grower, however, is not pest control but fertility . . . The key, Leo says, is to manage the soils as what they were originally, bush or forest soils."

Production innovations

Other innovations in kiwifruit production have focused on the layout and structuring of orchards. Kiwi vines are dioecious—they have male and female flowers on different plants—and in the early years of the industry growers set just one male vine in eight in an effort to maximize the available space for the productive female plants. Later this ratio was doubled to one in four, as it became clear that thorough pollination was critical to the production of top-quality fruit.

One of the first things the Whittles did was to ‘strip-male’ their orchards, making every other row fully male. Rows are 3 m (just under 10 ft) apart, with plants 5 m (16-1/2 ft) apart in the rows; the male plants are pruned back after pollination to give the females more space in the canopy. Next they removed the so-called internal shelters, leaving just the Cryptomeria hedge around the perimeter of the block. Kiwifruit vines are very sensitive to winds, especially when they’re young, but in established orchards the additional shelters have proven unnecessary, and may encourage disease.

Whittle sprays Bt to control leaf-roller caterpillar and uses a mineral oil product to suffocate a scale insect—always spraying in the late evening to avoid harming the bees that are brought in to pollinate. The top of every vine and trellis standard is ringed with a band of sticky tape, about 2 cm wide, to discourage climbing insects from entering the canopy, and a native plant known as kawakawa (Macropiper excelsum) has been planted at regular intervals through the orchard because Leo believes its peppery taste helps repel the passion vine hopper, which produces a honeydew that in turn attracts a fungal black rot. Conventional producers also typically apply a fungicide to arrest a fruit rot disease, Sclerotinia, but Leo has found that this is simply not a problem in an organic system. “I’ve been trying to convince my neighbors about that one,” he shrugs. “I think I’m almost there.”

Kiwis are a sensitive bunch: Hedgerows of Cryptomeria border the vines to keep breezes from entering the growing blocks--kiwis are very sensitive to wind.

The biggest challenge for the organic kiwi grower, however, is not pest control but fertility. The kiwifruit vine is a relatively heavy feeder, requiring lots of potassium as well as nitrogen. Conventional growers rely on chemical fertilizer, and the Whittles use a foliar seaweed product, but more importantly they have sought to improve the soils beneath the orchard.

The key, Leo says, is to manage the soils as what they were originally, bush or forest soils. “The kiwi is a forest vine—its native relatives grow in the forest in China,” Whittle points out. “Many people think of forest soils as poor soils, but they’re not, they’re just different from grassland soils. They can be enormously productive. They get lots of leaf litter accumulation, and they’re fungal-dominant, not bacterial-dominant.”

To bring out the natural properties of these soils and to mimic the kiwifruit’s native habitat, the Whittles cultivate a richer environment beneath the canopy. All prunings are left to dry down where they fall, and get chopped up the next time Leo runs the mower through (he mows the orchard just three times a year, twice lengthwise and once crosswise). The standing sward of rye, clovers, and fescues is increasingly varied with herbs like dock and comfrey, which help pull nutrients up from the subsoil.

Finally, after harvest Leo applies 5 metric tons per hectare (or 2.23 US tons/acre) of carbon-heavy compost, cooked up from annual trimmings from the 5-meter high Cryptomeria shelterbelt, cuttings of the grass headlands around the orchard, and occasional loads of fish carcasses from a local fish processor. “The fungi accumulate on the wood chips,” Leo explains; “that’s where they like to grow.”

The whole system is remarkably self-contained, and the results speak for themselves: when Leo brings a spade out to the orchard and slices out a square of earth, it’s soft, dark, and peaty, interlaced with vine roots and with a rich earthy smell. “I call this potting-mix soil,” he says, proudly.

"The difference in taste between organic and conventional kiwis, is readily apparent, the Whittles say: organic kiwis are denser and have much more flavor."

Although the fruit looks beautiful as well, Leo says it’s been a bad year weather-wise and they expect to get just 5000 trays per canopy hectare, as opposed to their usual 7000 (about 15,600 versus 21,800 lbs/ac). Conventional growers generally get around 10,000 trays/ha. On the other hand, organic kiwifruit receive a price premium of around 15 percent, and the Whittles report that they do less work now than they did as conventional growers. In time, moreover, they believe organic yields could overtake conventional ones. Diane observes, “We had to say to the vines, ‘This is the way you are to eat now.’ It’s taken some time for them to adjust.” The difference in taste between their kiwis and conventional kiwis, moreover, is readily apparent, the Whittles say: organic kiwis are denser and have much more flavor.

Organic kiwi growers are leading the way

As chairman of the NZ Certified Organic Kiwifruit Association, Leo works closely with Zespri to maintain and even raise organic standards. Zespri is considering opening a dedicated organic cold store facility, and sends a field officer around every year just before harvest to collect organic fruit samples near shelterbelt gaps or other likely points of contamination. (It’s the fifth year of the program, and they have yet to find any residues on organic fruit. “It says a lot for the care and consideration of our neighbors,” notes Diane.) Zespri has also been a leading voice in New Zealand’s anti-GE (genetically-engineered) crops campaign, securing a clause in the NZ government’s official report on GE, published in 2001, which may prevent the release of any GE horticultural crops.

"The kiwifruit industry is leading the horticultural sector generally, in other words, and organic kiwi growers are at the front of the kiwi grower pack."

As that position suggests, the whole industry is moving ever closer to organic. Since 1992, when a shipment of conventional kiwifruit going into Italy was rejected for excessive pesticide residues, growers across the spectrum have been rethinking production methods, with IPM (integrated pest management) strategies, for instance, now nearly universal. Conventional kiwi growers used to spray every three to four weeks throughout the season; now they spray just two to three times a season. Whittle’s been encouraging his neighbors to leave more litter under the canopy too—“they used to go for a bowling green under there,” he notes, “absolutely level and clean.”

The kiwifruit industry is leading the horticultural sector generally, in other words, and organic kiwi growers are at the front of the kiwi grower pack. Aren’t they in danger of eliminating their market edge over the conventional producers, then? “We sure are,” Leo replies, grinning ruefully. “But it’s worth it. The higher we can raise the environmental standard for the industry as a whole—for farming as a whole, the better.”

Laura Sayre has been working on organic farms and writing about agriculture since 1991.