Using soil probes for seasonal preparedness

Summary

To manage the climatic variability, along with increased input costs, more informed and timely decision making will be required by producers to maintain farm productivity and increase their farm business resilience.

Soil probe information has been used to inform decision making in other parts of the state in cropping enterprises for many years. Soil probe data has the potential to be valuable in grazing enterprises and their use has increased, however it is a relatively new tool for farmers to utilise in the east Gippsland region.

The aim of this producer demonstration site is to improve Gippsland farmers knowledge of soil probe information and to increase the use of the soil probe data to provide a better guide to decision making strategies in grazing enterprises through the development of seasonal trigger points, thereby improving management of climate variability impacts upon grazing enterprises in the Gippsland region.

Objectives

By December 2025 in the Southeast regions of Victoria the project will establish a minimum of 3 demonstrations farms, engaging 10 core producers and 300 observer producers to:

1. Demonstrate on three sites the correlation of pasture growth and productivity data with soil probe data and the value of soil probes for making informed seasonal decisions.
2. Use modelling to demonstrate an increase in pasture growth from more timely decision making in comparison to existing farm practice. Modelled decision making using soil probe date will lead to a hypothesised 10% increase in pasture growth
3. Run three workshops with 30 producers to discuss/develop seasonal trigger points to assist timely decisions including soil probe data. In the workshop situation, we will demonstrate the use of partial budgeting to show the impacts of delaying or bringing forward different decisions and their impact on the bottom line.
4. Extend and promote soil probe data from the network of 17 probes across central and east Gippsland through monthly updates in local media.
5. Have 100% of core members and 40% of observer members with improved knowledge, skills and confidence in accessing and basic interpretation of soil probe data, including understanding the soil moisture and temperature graphs and the use of the MLA tools for pasture assessment.
6. Expanding on the partial budgeting used in the workshops, the project will provide a CBA to demonstrate the
   benefits of timely decisions.
7. Widely disseminate the PDS results and learnings through targeted extension activities such as paddock
   walks, workshops and media.

Progress

Producers in East Gippsland operate in an increasingly variable climate where irregular rainfall, shifting seasonal patterns and low winter soil temperatures create major challenges for reliable pasture growth. The project demonstrated how soil moisture probe data can guide timely and informed management choices, improving decision making under these conditions. 

Soil moisture, temperature and rainfall were recorded and correlated to pasture growth rates at three sites; Bairnsdale, Buchan South and Omeo. Demonstrations including urea and gibberellic acid (GA) applications, grazing interval comparisons, improved versus unimproved pastures, and a time of sowing were undertaken at the three sites to identify opportunities to maximise pasture growth.

Results showed clear links between soil moisture conditions and pasture growth: soil temperature restricted winter production, while soil moisture drove growth through spring, summer and autumn. 

Improved fertility and pasture species doubled dry matter production at Omeo. Simulated grazing to the 2 ½-3 leaf stage in ryegrass increased overall yield by 18 t DM/ha (96% increase) at Buchan South over 26 months. GA applied below ambient temperatures of 15 °C, especially when combined with nitrogen, generated strong growth responses, and early sowing (early April) delivered the highest overall biomass compared with later sowing.

Extension activities—31 newsletters, field days and trigger point workshops—significantly increased producer knowledge and confidence, with widespread adoption of soil moisture probe data (100% of core producers) for grazing, sowing and fertiliser timing. These outcomes highlight the value of accessible, locally relevant soil moisture information in strengthening seasonal preparedness and reducing production risk.