Our Strategy

Our deficit irrigation strategy for wine grapes utilizes a proprietary computer model configured with vineyard-specific data supplied to us by the idividual grower. We input this information into our model along with current local weather data supplied by the CIMIS weather sensor closest to the subject vineyard, to obtain the initial irrigation starting date and daily run time. The daily run time is updated weekly to reflect current weather and vine development. We then supply this information weekly to the individual grower/subcriber via this website.

We use a form of the Deficit Threshold method to determine the initial irrigation start date. This method allows the vineyard to deplete the soil moisture accumulated during the rainy season to a critical level in order to induce a specific level of stress on the vines prior to the initialization of irrigation. The importance of stressing wine grape vines at this point is dicussed on the Deficit Irrigation page. This critical level of soil moisture is automatically calculated by the computer model and eliminates the need for complicated and time consuming in-field testing with expensive equipment such as the pressure bomb, neutron probe, etc.

The model calculates how much water per day a specific vineyard is capable of extracting from the soil. It then decreases that amount by a predetermined deficit rate to give the daily run time for that particular irrigation system. The grower simply adjusts the daily run time once per week. After harvest, the vineyard is irrigated at full potential in order to gradually remove vine stress and enable root system expansion until sufficient rainfall or complete leaf drop occurs.

Some growers stop irrigating prior to harvest to increase sugar concentration. We do not recommed this practice, as it can dehydrate the fruit and lead to premature harvest. Our stategy is designed to allow the fruit to ripen naturally in order to maximize hang time, resulting in greater phenolic production.

Our irrigation strategy is intended to be used only in healthy, established, fruit bearing vineyards. It is not recommended for establishing new vineyards, nor vineyards with root systems severely damaged by pests or disease.

Suggested Irrigation System Requirements

• Drip Irrigation
• Automatic control valves/controller
• Adequate water supply
• Access to this website