Farmer's Weekly (South Africa)
New kiwi fruit varieties promise export-led profits for SA growers
Across South Africa, farmers are looking to diversify their production bases by planting high-value crops that have export potential. Peter Turner, director of SA Kiwi Pollen, spoke to Jeandré van der Walt about new yellow-flesh kiwi fruit varieties that show promise in the Western Cape.
Approximately 40 years ago, a number of over-optimistic local farmers saw an opportunity for growing kiwi fruit in South Africa, and planted green-flesh kiwi ( Actinidia deliciosa) varieties here. Some burnt their fingers in the process, and today there is still some resistance to kiwi fruit production in the country.
Peter Turner, director of SA Kiwi Pollen, explains that the undesirable results obtained from the green kiwi varieties in the 1980s were a result of mismatched pollinators and the fact that the farmers chose incorrect varieties. Most green kiwi varieties have high chilling requirements.
In addition, growers didn’t have import price parity on their local fruit sales in the 1980s.
Much has happened since then, says Turner. “We now have a whole range of new varieties with lower chilling requirements than those that were attempted in the past, and we have the male plants to guarantee synchronicity. In addition, we’ve improved production techniques.”
He believes that kiwi fruit, particularly yellowflesh varieties ( A. chinensis) with low chilling requirements, hold good diversification potential for farmers in areas suitable for pome and higher-chill stone fruit in the Western Cape.
CLIMATE LIMITATIONS
Although Western Cape farmers could prosper from kiwi fruit production, Turner emphasises the importance of taking climatic conditions into consideration when thinking of growing the crop in the province.
“Prospective growers must ensure that they understand their local microclimates by researching their long-term [mean] chilling unit accumulation from May to September for the past five years to check whether the chilling units are suitable. Knowing this will enable them to choose the varieties that best match their chilling units,” he says.
Turner notes that chilling requirements for kiwi fruit range from 700 to 450 Richardson chill units. This immediately limits potential kiwi production areas in the Western Cape. However, the development of yellow-flesh varieties with lower winter chilling requirements, such as Soreli, Jintao and Jinyan, provide an opportunity for a slightly wider range of production microclimates than with the green varieties previously attempted.
Grabouw, Waboomskraal and the Langkloof in the Western Cape show good potential for these yellow-flesh varieties, he explains, as these areas experience adequate winter chilling, high humidity in spring, and drier summers.
ESTABLISHING AN ORCHARD
According to Turner, the optimal time to plant kiwi fruit is similar to that for apples and grapes, provided there is no frost. Kiwi fruit are sensitive to damage from wind, and production should therefore take place under shade netting. If the area is prone to late winter frosts and hail, netting is essential.
Kiwi fruit also require a training system that can support up to 100t of crop and vine loads. The netting and training system can be incorporated into the same structure.
Farmers should be aware that establishing a kiwi orchard requires a considerable investment, cautions Turner. Average spend is R1 million/ha for the capital, interest and production costs up to the first crop in year three.
Initially production yields are very low, but begin to achieve consistent levels from year three to year five of 10t to 15t, 25t to 30t and 35t to 45t respectively. If these yields are attained, the farmer will begin to break even between years five and seven.
Turner recommends obtaining a good rootstock before starting a kiwi orchard.
“At the moment, there are about four in South Africa. The Bruno rootstock has the longest history and the lowest chilling requirements.”
Currently, there is a two-year waiting list for plant material from nurseries that Turner considers up to standard.
Kiwi fruit is a dioecious plant, which means that the male and female reproductive organs appear on different plants and both sexes have to be planted. Turner recommends a ratio of at least one male kiwi plant for every six female plants in an orchard.
PRODUCTION CHALLENGES
Kiwi fruit can be an unforgiving crop. If you miss key activities within the production cycle, there isn’t much room for playing catch-up.
‘KIWI PRODUCTION COULD BECOME A THIRD PRODUCTION SECTOR WITHIN THE DECIDUOUS FRUIT INDUSTRY’
“The crucial areas that growers need to focus on are achieving adequate chilling units, winter and summer pruning, pollination, nutrition and maturity indexing,” explains Turner.
He adds that pollination plays a major role in successful kiwi fruit production. Nectar production in kiwi flowers is generally poor, resulting in low attractiveness to bees, so farmers have to learn how to work around this shortfall.
“An ideal-sized kiwi fruit weighs about 100g and contains up to 1 000 seeds. To achieve this size, growers should embark on the five-pronged pollination strategy of flower-thinning, cover crop management, artificial pollination, inclusion of bees, and the use of wind machines.”
Producers should also bear in mind that kiwi fruit plants are thirsty; they need almost 30% more water than apples do. Turner cautions against becoming disheartened by the plant’s water consumption, however: “If you look at your revenue to cubic metres of water, it will pay off.”
He adds that kiwi fruit is an intensive-management crop, similar to blueberry and apple, with the busiest period being from October to December and at picking, which starts in mid-March.
However, management costs per hectare are less than for tree fruit crops due to lower spraying costs.
“Currently, the incidence of pests and diseases in kiwi crops is low relative to other fruit crops, such as apples. You can easily farm kiwis organically.” Turner notes that bacterial canker, which is caused by the bacteria Pseudomonas syringae pv. actinidiae [Psa], has caused great harm to the international kiwi fruit industry. Fortunately for local growers, the disease is not present in South Africa.
MARKET OPPORTUNITIES
According to Turner, South Africa’s current effective hectarage of kiwi production is no more than 300ha, and the country imports 95% of its kiwi requirement, which is 6 000t to 7 000t per annum.
He adds that there is an excellent opportunity for South Africa to become a self-dependent kiwi producer, and the country is well placed to supply African and Oceanic island destinations. Also, South Africa is the most northerly production region in the Southern Hemisphere, enabling it to supply fruit to the market earlier than other Southern Hemisphere producers such as Chile, which has 9 000ha planted to kiwi fruit, and New Zealand, which has 12 000ha.
For South African producers to command high prices, they need to establish good partnerships with Northern Hemisphere kiwi-growing and marketing companies, says Turner.
“Another opportunity for South African kiwi producers is to become a Southern Hemisphere supplier to leading Northern Hemisphere players seeking to supply retailers year-round with both greenand yellow-flesh kiwi fruit.”
Turner is convinced that South African kiwi growers have a bright future.
“I believe there are regions [in South Africa] where kiwi production can become a third or fourth production sector within the deciduous fruit industry. I’m particularly excited about varieties such as Soreli, Jintao and Jinyan, [which have shown] excellent performances in commercial, semi-commercial and trial sites in multiple production microclimates across the country.”
He adds that with South Africa’s high number of sunlight hours, lower production costs, favourable geographical location, and Psa-free status, the local kiwi industry has the potential to grow to between 1 500ha and 2 000ha within the next few years.
Email Peter Turner at peter@sorelikiwi.com.
‘THE MAIN FACTORS ARE ADEQUATE CHILLING UNITS, WINTER AND SUMMER PRUNING, POLLINATION, NUTRITION AND MATURITY INDEXING’