Given the irrigation season has now kicked into gear, we thought it would be useful to use this article to run through the costs and benefits of monitoring, understanding, and managing soil moisture when irrigating.
Let’s start with the costs; a quality telemetered soil moisture probe is typically between $3,000 and $3,500 installed, the Bluetooth equivalent (manual download) is around half this price. Many question these costs and whether they will see a return – can the cost be justified?
To answer this, you need to assess the likely benefits of fine tuning your irrigation; these come from both minimising operating costs and increased productivity.
Table 1 provides an indicative dollar value per hectare based on a 1% increase in yield for the common crops found in Canterbury; the yield and income values used for these are conservative. The dairy income is based on an 11:1 ratio of kg/DM to kg/MS and the current pay out; the beef and lamb finishing income is based the kg/DM required to finish each livestock type and the current sheep and beef schedules.
For a 200-hectare farm (the average farm size in Canterbury), the cost of a quality soil moisture probe is easily paid for within the first season with just a 1% increase in yield or production. For many farm systems multiple probes could be purchased and paid for within the first season, noting that most farms require between 2 and 5 probes to provide sufficient data for good irrigation decision-making depending on soil type, crops grown and the irrigation system.
Table 1: Production Benefits of Soil Moisture Monitoring
In addition, there are also cost savings through minimising irrigation operating costs (starting and stopping irrigation at the right time), the benefits from this are shown in table 2 for three pumping scenarios – the assumptions used are conservative. For a 200-hectare farm the cost of a quality soil moisture probe is again paid for within a season, and for groundwater pumping scenarios multiple probes could be purchased.
When the potential production and operating benefits are combined, purchasing a soil moisture probe for your property becomes a no brainer!
Table 2: Operating Benefits from Soil Moisture Monitoring
Primary Insight are specialists in soil moisture measurement, if you want to find out more about soil moisture monitoring, need support with trouble shooting an existing installation or would like know how to read and use your soil moisture data for irrigation decision-making, we are here to help you.