Many of you would know that we had a very wet winter in Victoria last year, culminating in a December rainfall that broke every record.
This is followed by a period of mad shoot growth in November and December, when grape growers spend their days removing unwanted shoots from the single cane or spur for each vine that has been laid on the base wire cordon.
The shoots are removed for two main reasons: to discard shoots that are not pointing upward, which helps manage canopy structure; and to thin shoots so that the vine isn’t overloaded with fruit.
The rule of thumb is that in a good season a healthy vine can ripen between 16 and 20 bunches to the quality demanded by fine winemaking. Of course in areas like Sunraysia, shoot density is much higher and consequently, there is far more fruit grown per vine but of lesser quality than say in the Yarra Valley. Since each shoot will develop two bunches, good growers will leave between eight and ten shoots on each vine.
Young shoots are soft and vulnerable to attack by the two main vineyard killers, powdery and downy mildew. The huge rainfall in December created many high-risk periods where moisture, humidity and heat combined to produce a field day for the dreaded pair. Heavy rain also swept protectant sprays from the vines, which were left defenceless, and where the rain continued, spraying was impossible, meaning that disease propagation was extremely rapid.
Many vineyards lost substantial proportions of their crops mainly to downy mildew, sometimes in cases where it was impossible to stop, and in other cases because the spray regime of the vineyard concerned wasn’t well planned.
But – and here was the silver lining – in vineyards where the vines were protected, the result of the rain was a magnificent fruit set and bunch shape, and size which had not been seen for years. This was followed by a virtually rain-free February and March, with steady warm weather through the vintage period.
Look for some wonderful 2018 Yarra Valley wines when they are released in 2019 and 2020!