Founded on February 1700, Vergelegen, meaning “situated far away”, is a world-class wine estate enjoying 3,200 Ha of perfect biodiversity mix, down The Helderberg mountains and the Lourens River. Its 123 Ha of vines are mainly planted with Cabernet Sauvignon (30%) and Sauvignon Blanc (30%).
In 1998, the anglo-american owners decided to change the managing and viticultural teams to infuse a new vision for their wine. This innovative spirit is perfectly embodied by André Van Rensburg character, who was appointed chief winemaker 20 years ago. Gathering a team of experts, André explored ways to cure the leafroll virus striking his vines with the vision to become “the first virus free property in the world”. He also anticipated climate change and engaged significant work to make the domain self-sufficient in water supply, with quality wine and a controlled biodiversity. This is the result of a 20 years preparation detailed below.
“Leafroll is the new phylloxera”
The leafroll virus is a world famous disease, discovered in 1936, defined as follow by André Van Rensburg :
“Grapevine leafroll disease (LR) is a serious disease of grapevine worldwide. Grapevine leafroll-associated virus 3 (GLRaV-3) is the most prevalent virus associated with this disease in South Africa and, despite a successful virus-elimination strategy within a certification scheme, spreads rapidly in local commercial vineyards.” (Control of Grapevine Leafroll Disease Spread at a Commercial Wine Estate in South Africa: A Case Study – Van Rensburg, 2013)
The virus has always been neglected by farmers as it is not instantly fatal to the vines. No one has ever considered the idea of a possible curation, as André told us during our interview: “Because of the ubiquitous nature of the disease here it has always been considered something grapevine growers have to live with, and not as an entity that could be controlled.”
Yet, infected vineyards decline in berries quality and quantity, because of a delayed fruit maturation with reduced sugar content and color. This undoubtedly leads to lowered crop yields and also reduces drastically the longevity of the vines.
André was the first winemaker trying to understand the underlying reasons of why the leafroll virus was so hard to remove.
Assisted by his wife Maritza who performs around 18,000 vines analysis a year, Dr.Pietersen as Chief Virologist and Dwayne Lottering as Assistant Winemaker, André built up a dedicated team to implement his innovative vision to cure the Vergelegen vineyards from the leafroll virus.
They elaborated a clear step-by-step plan to heal any infested vine blocks:
- All new vines have to be treated with a systemic insecticide.
- Viruses vineyards from red grape varieties need to be replaced by treating the old infected vines with herbicides to kill them before removing them.
- As many of the white cultivar vines were still producing good quality berries, vines were individually replaced as soon as they no longer delivered great wines.
- Performing tests following ELISA laboratory technique to control the invisible symptoms on certain cultivars. Symptoms can’t be seen by human eye on certain types of white cultivars and it must be remembered that up to the middle nineties close to 80% of all plantings in South Africa were white grapes! (André Van Rensburg, in a note Vergelegen Estate – Leafroll Virus Management, 2012)
By using this method, André and his team not only almost doubled their yield, but also improved the colour, flavor and structure of their wine. They reduced the infection rate of freshly planted vineyards (13 years) to 0.027%, and are getting closer and closer to a total eradication in the domain. André likes now to claim he runs the “only virus free property in the world”.
The main challenge is now to be able to shift from chemicals to biological methods, in order to cope with their unique biodiversity policy.
The Fynbos case: balanced biodiversity is the key
Anticipating climate changes, André started to work on the harmony of the 3,200 Ha and hired a flora and vegetation specialist to help him in this task. They decided to eradicate any alien vegetation on the property and plant the original species that used to grow in the area.
Pines and Eucalyptus, consuming too much water – almost 200L/tree/day – were all removed and replaced by Fynbos, a typical vegetal from the Western Cape coast.
Although it might be an expensive solution, the property lives in a more natural environment and a low natural water consumption. That’s the only reason why they still have a water stream going through the domain, according to Dwayne Lottering who gave us an amazing tour.
Facing the drought
Talking about water consumption and in line with the climate change vision of André, the main dam, originally built by the previous owners in the 90’s, was renovated and dug deeper, while two others were also constructed, ensuring the water self-sufficiency of the domain.
90% of the vineyard has now the facility to be irrigated, but André only uses this solution for emergency cases. With 2018 being the third drought in a row, Vergelegen was perfectly ready to face this extreme weather conditions on the long term, with the capacity to irrigate with water coming from his own dams, independently of the government’s water restrictions.
From experimentation to fame
We were stroke by the modern vision conveyed by André during the interview. Explaining the different parts of his strategy for more than an hour, it looked like the entire method was natural. But among the 12 winemakers we met, André is the only one to tackle these issues with method and process. Added to a unique terroir close to the ocean that gives cool air flowing, naturally abundant water from the mountains and soil made of decomposed granite with high good water retention properties, Vergelegen seems ready to face the climate change challenges of the next decades. That’s maybe why the world-famous French wine consultant Michel Rolland decided to join the adventure few years ago.