The MEC for the KwaZulu-Natal Department of Agriculture and Environmental Affairs (DAEA), Mtholephi Mthimkhulu, once said the province’s agricultural potential is so diverse there isn’t a crop in the world that couldn’t be grown somewhere in KZN.
Others have had the same idea. Both South Coast businessman Wally Archer, in 1992, and fruit specialist Dr Clive Kaiser, in 2000, experimented to see if various varieties of common grapevine (Vitis vinifera) would grow well enough in KZN to be used for winemaking.
Trial and error W ally attempted trial plantings of Cabernet Sauvignon, Shiraz, Merlot, Chardonnay and Muscadel varieties at the relatively warm Sunwich Port. In a review of the KZN wine industry on The Stables Wine Estate’s website, Clive notes these weren’t very successful because the vines received insufficient chill units, delaying foliation. “Wally looked at vines more suited to his climate, and after a study trip to Australia in December 2003, he imported a Vitus labrusca hybrid, Chambourcin, currently being cultivated at Leopard Rock in the Oribi Gorge area,” he writes.
Clive himself joined the KZN DAEA in 2000 after working in the Australian and UK fruit industries, where he obtained experience with vine growing and winemaking. He was convinced KZN could produce wine grapes and submitted several business plans to the KZN DAEA’s senior management. ith the support of the late Dr Brian Louw and Rob Osborne, both also of the KZN DAEA, Clive got approval to import several wine grape cultivars from the Western Cape – Cabernet Sauvignon, Merlot, Shiraz, Pinotage, Chardonnay and Sauvignon Blanc – each on Richter 99, 110, Ramsey and Mgt 101-14 rootstocks. In October 2000, 4 000 plants were distributed to growers in the KZN Midlands area for the trial.
“KZN’s climate and soils are generally very different to the Western Cape, which is considered the home of wine production in SA,” explains Rob, currently a specialist researcher in horticultural science for the KZN DAEA. “KZN has a summer rainfall climate as opposed to the Western Cape’s winter rainfall climate. We also had to find areas that didn’t experience severe hail, excessive summer temperatures and rainfall, and extreme winter cold and frost.
Hail can damage the vines and grapes, while a combination of hig h temperatures, rainfall and humidity can promote disease. Extended periods of very cold weather and frost stunt the vines’ growth.” T he initial trials faced several problems. Each grower was given only 200 to 400 vines, too few to justify the intensive management needed to establish a commercial vineyard. “To be honest, the KZN DAEA also lacked the experience to give growers adequate vine management advice,” admits Rob. “The experiment taught us that it was going to be a lot more difficult to grow grapes in the Midlands than the Cape, and that we’d have to develop different management strategies.” In May 2001 Martin Hill, the owner of Bracken Estates outside Greytown, and one of his managers, Gordon le Roux, met with Clive to discuss planting grapevines on their farm. In August 2003, they planted six vine cultivars on 15ha, which developed so well that Bracken Estate’s current 18ha of grapevines is considered the mainstay of the KZN wine industry. Clive left the KZN DAEA in 2002, but Rob revived the research programme in 2004.
He established a larger-scale commercial trial with Ian Smorthwaite on Ian’s farm in Lion’s River. At the same time, cultivar trials were established at Cedara Research Station. Currently, 19 grape cultivars are undergoing evaluation. The results from the initial trials prompted other innovative Midlands landowners to invest in growing grapes and in wine production equipment. All intend to put KZN firmly on SA’s, and even the world’s, wine map. Already, several have produced wine from their own grapes, or from grapes grown in KZN, albeit often on a limited or experimental scale. It’s only a matter of time before their wines are tasted throughout the country and beyond.
Distinctive challenges Rob’s research, together with feedback from the growers, has revealed the challenges particular to growing vines in KZN. “The KZN DAEA has a sophisticated bioresource unit programme, and has produced a crop model showing optimal wine grape production areas in KZN,” he explains. “Vines require specific climatic conditions to produce grapes of sufficient quality to make wine. The growing season for wine grapes begins in spring when the plants have received enough chill units to come out of dormancy, and when temperatures are conducive for bud-break. Vines don’t grow at below 10ºC and need temperatures of 15ºC for optimal flowering and fruit set. “To produce grapes with enough sugar for fermentation in the winemaking process, enough heat must be accumulated during the growing season. Very warm areas can produce table grapes with high sugar levels, but their acidity is generally too low to produce quality wine.
“Late spring frost will hurt flowering and fruit set, while temperatures below -16ºC for extended periods will kill vines. Avoid areas subject to severe frost.” A more unusual management challenge is soil fertility. Many KZN soils are so fertile that grapevines grow too vigorously, hampering fruit development. Rob explains, “Overgrown vines shade the fruit, and the plant puts more energy into leaf production than fruit development. “Canopy management is critical. The vine should be shaped to have just enough leaves for adequate photosynthesis. Pruning should also allow airflow through the vines so excessive humidity doesn’t build up around the grape bunches. Because vine growth is so vigorous, canopy management is also more labour intensive.”
The right choices Today Ian, who participated in Rob’s 2004 commercial trial, is a grapevine grower and fledgling winemaker on Abingdon Wine Estate. A passionate proponent of KZN wine production, and addicted to grape growing and winemaking literature, Ian has identified factors influencing optimum production. “This journey is an immense learning curve,” he says. “I don’t believe I’ll ever stop learning but, for the seven years I’ve been researching grape and wine production, and for the four years I’ve been growing vines, I’ve learnt you have to adapt the basic principles to suit KZN’s diverse climatic conditions.” Ian feels grape varieties such as, say, Chardonnay, which have traditional harvest dates, are less suitable to KZN. January is usually wetter than February, as is March, with April drying up again.
It therefore makes sense to plant varieties such as Sauvignon Blanc that are harvested in February, or late-ripening cultivars such as Cabernet Sauvignon, harvested in early April depending on altitude and the possibility of early frost. However, Ian cautions that when growing late-ripening varieties like Cabernet Sauvignon, Mourvèdre, Nebbido or Petit Verdot in a summer rainfall region, extended hang time could, during a very wet summer, open the door to sour or grey rot, making the crop useless for wine production.
“In our Lions River area white grape varieties, like Chardonnay, can be risky as they’re susceptible to downy mildew, which will infect the vineyard if the rainfall on any given day is over 10mm and the temperature over 10ºC.” Ian speaks from experience, “It’s taken us four years to rehabilitate our Chardonnay vines after a bad bout of this disease in 2004. A strict fungicide spray programme is essential.” Ian has also found that cold conditions curtail the sugar accumulation of late-ripening grape varieties as heat units taper off in autumn and there’s the risk of early frost. Rob says these grapes normally reach optimum sugar levels three to four weeks earlier in the Western Cape than in KZN.
“Thin-skinned grape varieties, such as Pinot Noir and Merlot, should be treated with caution here because of their low resistance to infection,” warns Ian. “Their early ripening might also cause problems, as January rains can cause the berries to swell and burst, allowing bacteria to infect the crop. Growers want their harvest to be as dry as possible – a difficult challenge in this part of the world, and very dependent on where a vineyard is situated and how good a grower’s canopy management skills are. “However, it’s still too early in our learning process to be certain which varieties work best for particular areas.
Most vines will grow in the Midlands, but we still have to learn whether the fruit will ripen to acceptable sugar levels or just rot.” A Midlands wine route “With an extended growing season and fertile soils, we should be able to extract more flavour from the berry and create a unique wine,” says Ian. “There’ll always be critics, but time will tell. Good wine is being made here in KZN by using our own grapes grown on our own land.”
Rob and Ian agree that site and cultivar selection are critical, and growers should keep their vineyards and wineries small and manageable in these early days. Staff skilled in grape-growing and winemaking are limited here, and they believe that when the KZN wine industry has developed more experience, and formed supportive industry associations, the province will ultimately have an active Midlands wine route. Contact Rob Osborne on (033) 343 8342 or e-mail [email protected]; or Ian Smorthwaite on (033) 234 4335, or [email protected].