🌿 Drip irrigation

Drip irrigation is a way of supplying water to vines through tubes that release it drop by drop at emitters, so only part of the soil around each vine is wetted.

In a six-year study of Sauvignon blanc in Washington State, drip used less water than flood or sprinkler irrigation while still giving good vine vigour, fruit production and quality. Drip suits hillsides and soils where water soaks in slowly, where flooding or overhead sprinklers are impractical. It costs more to install and needs more management, and salt can build up in the smaller wetted area.

Watering affects the wine. Berry size is set largely by the water supply before veraison, the start of ripening. A planned moderate water deficit before veraison, called regulated deficit irrigation, controls shoot growth and, in red varieties, gives higher phenolics and tannins, which add flavour and complexity. In Europe, regional rules often restrict or forbid applying water during grape ripening.