Vintage Report: December 2001
The Cape Winelands experienced an abundance of rainfall quite late in the winter season, this year. For the first time in four years dams were overflowing and as some growers said, even the water table is overflowing.
Although this is obvious good news, with prospects of ample water supply and a cool ripening season, the humidity and heavier canopy growth offers favourable conditions for the downy mildew spores to develop.
Downy mildew can still be controlled when it hits the leaves, but once mildew occurs, during flowering or when it infiltrates the actual bunches, later in the season, the battle is lost.
"This year some of the damage was experienced during flowering, with later varieties being more severely damaged. This was due to the wet conditions, excessive dew during the nights and heavy fog in the morning. However, the actual extent of the infection will only be apparent after veraison, approximately one month from now", says Victor Sperling, viticulturist at their family farm, Delheim.
In the Stellenbosch area early infection was identified on Chardonnay, Pinotage and Shiraz leaves. The variety with the highest level of infection is Cabernet Sauvignon, but this has been limited to certain vineyards. In Paarl, the downy mildew pressure is the worst in 5 years, although only a 10-15% drop in production volume is expected. There are a significant amount of vineyard blocks that are infection free, mainly due to those farmers' quick and thorough reaction on warnings earlier in the season.
International viticultural consultant, Phil Freese, reports very little damage in the vineyards he has been working with. "As with any vintage, the growers had to read the conditions and react accordingly." Pieter Ferreira, winemaker at Graham Beck in Robertson, has insignificant amounts of downy mildew and has it under control, as is the case for the rest of Robertson. Winemaker of Hermanus based winery Newton Johnson, Gordon Johnson, says that Walker Bay did not have as much rain as the Stellenbosch / Paarl area, with steady winds from the ocean drying up whatever moisture there were in the canopies, thus creating unfavourable conditions for the spores to develop.
At Rustenberg in Stellenbosch, resident viticulturist Nico Walters, is mainly concerned about their Cabernet Sauvignon vineyards, which seems to be the case in the all the areas.
Andries Tromp, who heads up the Integrated Production of Wine scheme (IPW), a world first for the sensible control of vineyard maladies with specific regard to environmentally friendly products, says that a complete program has been allowed for in the IPW program for conditions like we are experiencing this year. Tromp is in agreement with Phil Freese that the necessary preventative measures have been taken as soon as the conditions were diagnosed. "The types of fungicides used are all environmentally friendly, specifically targeting the relevant problem in the vineyard", says Tromp.
"Growers needed to be extremely vigilant, in order to get the timing and thorough covering of the foliage right, with a little bit of luck thrown in, of course!" concludes Freese.
But given that we were expecting a record crop after the ample rainfall earlier this year, the drop in production will be insignificant, and in line with previous vintages.