About PIWI Grapes
PIWI Grape Varieties
Why PIWI Grapes?
Though fungicides are currently effective at controlling fungi, nature will always move faster than a chemist in a lab. It is unlikely we will be able to develop new fungicides quicker than fungi can evolve resistance. Using natures natural control is the best way to fight mildew.
Fungicides also have negative impact on the environment and the profit margin. If they kill the fungus on the vine, these fungicides will also effect the natural fungi in the soil. And spraying vines 8 to 12 times per year can get quite expensive, so having vines that defend themselves is good for everyone.
When dealing with fungus in vitis vinifera, sprays are a requirement, though for safety reasons vines cannot be spray for a period of a few weeks before harvest. If the harvest period is wet, this will allow fungus to thrive and that fungus on the grapes will effect the flavour of the wine (see Laurot and Markus). PIWI grapes offer an advantage in this regard because their natural defences prevent mildew from getting out of control and effecting the flavour of the wine.