The grape industry faces environmental sustainability challenges concerning the use of water, fertilisers and pesticides, energy use, greenhouse gas emissions and the impacts of climate change.

Irrigation for grapes has traditionally been used to supplement natural rainfall, to ensure adequate growth and productivity from their vines.

Changes in soil and climate dictate that substantial amounts of water have to be applied. Because of an increase in water shortages, water use efficiency is a priority for the industry. Harnessing water technologies not only reduces energy use, improves efficiency and saves production costs, but also matches the crops’ water requirement contributing to yield and quality improvements.

Watermetrics stepped into vineyard management in the 20/21 season at Tyntesfield when we installed our equipment and applied our programmes. This resulted in encouraging progress around generating data to manage water and fertilizer applications.

First, we installed 800mm soil probes. These read both temperature and moisture at 100mm intervals and reports in 15 minute intervals. The presentation of the lines on the graph gives a clear picture of where a water application has got to in the soil profile, and shows obvious overwatering. This is beneficial in calculating the irrigation amounts so that water gets to the effective root zone.

Secondly, we measured the water applications, recording the amount and timing of the applications.

Finally, we gathered comprehensive, paddock specific climate information including rainfall collection. This equipment predicts the coming seven days’ weather, including the important evapotranspiration.

While it is great to have all the data, there’s also room to put it all together to so that effective management decisions can be made.

We used our partner Swan Systems to pull all this together and this model provided many advantages.

We set targets for nutrient levels at each growth stage, and could use the programme to record and modify applications as required. By connecting this with forecast weather and existing temperature, moisture, and planned irrigation, we could define the appropriate time to make the correct applications.

We defined the soil and its drainage and water holding capacity, and then we defined the crops’ desired moisture levels at each growth stage. Specific agronomic information such as midday stem water potential can be utilised in the settings.

This information was gathered from the grower and the agronomist, and related to the comprehensive nutrient and water information resident in the Swan programme. Any required adjustments for the specific variety or site were included.

The Swan Systems programme then sets a water budget depending on water volumes able to be used. It calculates the amounts of water required to meet the set targets and includes in this the predicted evapotranspiration and rainfall. It details the day and amounts to be applied, information that transfers to cell phones.

At Tynetesfield we set a desired target for the root zone of 31% moisture and allowed an operating zone from 27 to 33%. The application issues warnings if those limits are approached.

For the season we easily stayed within the limits, and were able to keep the moisture close to requirement. This takes moisture stress out of the equation, limits disease problems, and increases the crops’ ability to reach its potential, which is far less likely if fluctuations were allowed to occur. From the factual information gathered the effects of inadequate irrigation were clear, as were the difficulties of getting it back to where it should be. The information generally meant earlier applications with less water than would have been normally applied.

There is also comprehensive daily data history that can be printed as a PDF. Analysis of this pinpoints mistakes and better ways of doing things for a future crop.

We believe this application will be a hugely beneficial and important reporting and management tool. It helps address many of the environmental/water problem areas in grape growing, and contributes to water and cost savings as well as catering for optimal crop requirements.

Contact Richard Campion Agronomist at Watermetrics if you would like to discuss this further.

Phone: 021 199 1260

Email: richard.campion@watermetrics.co.nz