Fussy crop does fine in Wai-iti

Kumara farmers move south

SUE O'DOWD

A former Northland couple have just harvested their first commercial crop of kumara in Taranaki.

Gavin and Sue Stilwell traded the warmth and humidity of Dargaville for a 154-hectare Wai-iti farm more than a year ago, bringing with them decades of cropping experience.

They had been looking for an orchard in the Bay of Plenty, but opted for the Wai-iti block after visiting friends there.

"It was in our price range, although it needed a lot of TLC," said Mrs Stilwell. "It presented a bit of a challenge.

"I love it here. It's a nice climate - two to three degrees warmer than New Plymouth."

Taranaki's low humidity also made it more pleasant than Northland.

The Stilwells grew the world's most produced root crop, sweet potato, for 18 years in Northland where their 18ha yielded about 400 tonnes of gold kumara annually.

Their Taranaki crop is small by comparison, with the recent harvest netting 20 tonnes from 1.6ha. They grew four varieties - owairaka red for roasting, tokatoka gold for baking and mashing, beauregard orange and their own unique variety, which is sweet, has creamy pink flesh and can be steamed, roasted or boiled.

They have a contract to sell their pre-packed kumara under their Awatotara brand at New Plymouth's Pak 'n Save.

The kumara are not sold loose so that buyers can recognise them as a product of a particular grower, and for traceability.

"It's a challenging crop to grow, but it's good to work with. It offers a reasonable return and a good lifestyle," Mrs Stilwell said. "The weather always has the final say."

The process begins with the establishment of seed beds with river sand. Seed from previous crops is planted under plastic cloches.

After four to six weeks, the sprouts are cut off above ground and planted in raised beds, pre-moulded by a rotary hoe, and watered for a couple of days.

"It's beautiful soil here, just gorgeous," said Mrs Stilwell.

Mr Stilwell said the moulds kept the soil temperature at the optimum level of 18-20 degrees Celsius in the main growth period between December and February.

"There's no roots when they go in. But once the roots are established - within a week - the plants don't need a lot of water."

Weed control was vital and the couple have been surprised by the rapid growth of weeds here, particularly nightshade, inkberry and red shank.

They sprayed with paraquat, which, as a desiccant, did not stay on the kumara plants. Kumara must be kept weed-free to prevent smothering.

Mrs Stilwell said the couple would have to alter their weed management this season.

The plants were also checked regularly for disease, bugs and insect damage. "We try to avoid spraying. We didn't have to spray for bugs," she said.

After a growing season of about 130 days, the kumara were bulk- harvested in April.

The tops, which grow to about half a metre high, were chopped off before the kumara were dug up.

The kumara were picked up by a machine and put in buckets, then tipped into half-tonne bins and put into a storage shed for heat-curing.

Brushing rather than washing helps them keep and they can be stored for up to 18 months.

"If they get bruised, they go rotten. You can't treat them like potatoes. Be gentle with kumara. Their skins are soft when you first dig them," Mr Stilwell said.

While they were pleased with the quality of the crop, they described their 20-tonne yield as average, after the ground temperature fell in early March.

"Kumara are very temperature- sensitive," he said.

Almost 100ha of the Stilwells' property is leased for grazing, a QEII National Trust covenant has been established over 52ha and the remainder is planted in avocados, passionfruit and kumara.

The couple planted 386 passionfruit plants under cover in a 0.4ha orchard in February.

They first had to establish an A-frame timber structure - with 10km of wire - to support the foliage and fruit. The structure is covered by hailcloth to lift the temperature within and to stop wind and hail damage.

"It's a high-risk, high-return crop and expensive to set up," Mr Stilwell said.

Passionfruit was susceptible to fungal disease, and the plants lasted only six to seven years, so replanting would start in five years' time.

The plants are pruned and tied weekly at present, but pruning will increase once flowering begins in October. Fruit would be picked from February to October and would be exported.

The ground beneath the passionfruit plants was bare because hygiene was paramount. Mulch was not used because it posed a disease risk. Disease could wipe out an orchard in a week.

Initially, the plants were hand- watered, but Mr and Mrs Stilwell expected to install irrigation.

"People do things a bit differently in Taranaki," said Mr Stilwell. "Here you seem to plant it and worry about it later."

He acknowledged that he missed the infrastructure and the wealth of horticultural experience available in Northland, but also appreciated the support they had received from local growers.

The Wai-iti property also has 850 Hass avocado trees in a 9ha orchard.

Mr Stilwell said they had had a lot of support and encouragement from other avocado growers in the province. "It's a learning curve for us because we've never grown them before."

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