It’s that time of year when it’s useful to find 30 minutes in your life to reflect on the irrigation season. What went well and why? What could have been done better, and how could this be supported?
In doing this it’s useful to think about the irrigation equipment, alongside the timing and amount of irrigation applied. For irrigation equipment the following information is of value. How much time and money was spent operating the irrigation system? How often were there equipment issues during the season? How much time and money was spent on maintenance (or needs to be spent)?
Most farms can track the direct costs relating to maintenance through their P+L reporting, however unless specifically recorded, time spent, and other indirect costs can be more challenging. Given the current operating environment, understanding the true cost of irrigation to the farm business is essential if farm operating costs are to be minimised. For example, identifying components that need replacing or that could be upgraded to reduce operating costs, or accurately understanding the cost-benefit of a capital irrigation investment that has the potential to greatly reduce staffing requirements.
For the timing and amount of irrigation, it’s always of benefit to look at irrigation in relation to the climatic data – the soil moisture trace in relation to local rainfall and evapotranspiration. Some soil moisture service providers make this an easy task, for others it’s not. This is the main reason why we advise those wanting to purchase a soil moisture sensor to always look at how the data is displayed on the website and whether it provides analysis, rather than purchasing on price.
The diagram opposite shows an example analysis from the Sentek IrriMAX Live website. This provides the PET and rainfall over the season, a stacked trace of each sensor down the profile, and the irrigation management trace (combined readings of the sensors in the crop rooting zone). In addition to this, IrriMAX has an irrigation analysis feature. This shows the depth at which the plant is extracting water alongside the effectiveness of each irrigation (and rainfall) event.
The irrigation analysis is from my home raspberry block. From this there’s a period during mid-January where the irrigation controller was set incorrectly and ended up irrigating every day instead of 3 times per week. Unfortunately, as it’s a Bluetooth not web-based controller and I was away there was nothing that could be done about this at the time. When I came back and sorted the controller out, irrigation then got back on track… it then rained! The irrigation analysis feature in IrriMAX, which can be set up to run in real-time, made identifying this mix-up easy.
Primary Insight are specialists in soil moisture measurement, if you want to put in place reliable and accurate soil moisture monitoring on you farm, need support with trouble shooting an existing installation or would like to understand how to correctly setup, read, and use your soil moisture data for irrigation decision-making, we are here to help. We’ll also be running a couple of free irrigation workshops in April. Check out the event listings on our website for more information on dates and locations www.primaryinsight.co.nz. You’ll also get a certificate of attendance that satisfies your Farm Environment Plan irrigation training requirements.