Accurate localised growing-media moisture data: what can it do for me?
There’s a lot of talk about “big data” at the moment; the kind of data that is collected by satellites or huge sensor networks, processed in vast quantities in the cloud and made available to commercial growers for decision making.
There’s no doubting that big data is having a huge impact on our lives and will be increasingly important in the way we farm going forwards (in all aspects of the supply chain, not just cultivation).
However, it’s important to note that while big data has many advantages, it can also have its limitations.
For many applications growers will find that improving their crops, reducing water usage, countering environmental damage, and meeting legislation requirements will require highly detailed and localised growing-media and meteorological data. In many cases “big” data is likely to be just too big, too vague.
For many years scientists at NIAB EMR have been exploring the benefits that automated precision irrigation systems can have on cultivation of soft fruit. The real-world results of their research have been so encouraging that they have worked closely with commerce to make the software and hardware technologies available to commercial growers, to improve their bottom line.
The WET Centre was developed to meet this goal, being both an evolving research project and a demonstration centre for commercially available “best practice” equipment.
The key thing is that these automated irrigation systems only work well if they are fed by accurate and reliable data that is specific to the local conditions (in this case substrate moisture and polytunnel atmospheric conditions). To put it plainly, the system is only as good as the data that powers it.
The moisture content of the substrate (in this case ‘coir’) is among the most critical data for any automated precision irrigation system, so accurate and reliable sensors – positioned strategically in grow bags across the polytunnels – are required to achieve meaningful results.
An important benefit of localised sensor data relates to the speed at which it is available and can be acted on.
In the case of substrate-grown strawberry, raspberry and blackberry in protected environments, this “timely” period for responsive action can be very short. Berry size and quality can deteriorate within a matter of hours under sub-optimum growing conditions.
In addition, online data viewing platforms can send the real-time localised sensor data directly to mobile phones (in the form of meters or graphs) so that growers can easily stay up to date with conditions – 24 hours a day, seven days a week – regardless of where they are.
Localised sensors also enable understanding of how slight variations in the microclimate across the growing area affect consistency of yields and berry quality, and how growers might be able to manage these better to optimise productivity and quality.
The outputs from the WET Centre project are exciting – achieving less run-off and improved water and fertiliser use efficiencies – resulting in less wastage of key inputs and lower emissions. Results suggest that growers could perhaps reduce inputs of water, fertilisers, pesticides and energy by up to 20 per cent without affecting marketable yields and quality.
By eliminating unplanned water deficits, commercial trials have also shown that the WET Centre’s precision irrigation system systems can deliver higher yields compared to manual scheduling methods; yields of Class 1 strawberries being up to 10 per cent higher.
The importance of accurate local root-zone moisture data also relates directly to the demands of environmental legislation. Recent government reviews dictate that all growers who use trickle irrigation now need to apply for a licence, and that new licensed volumes will be restricted to their “peak historic abstractions” over the past seven years. The implications of this licensing system are that in order to maintain industry growth (currently around 15% per annum), commercial growers will need to make limited amounts of water go further. This is exactly what the scientists at NIAB EMR have managed to achieve, using precise substrate water content data.
So, to directly answer the question posed by the title of this article, what can accurate root-zone moisture data do for me? Well, if you are involved in cultivating soft fruit the answer, hopefully, should be clear. For other growers and farmers, the same basic principles apply: high-quality, localised, measurement of your soil or substrate conditions is a prerequisite of any effective automated irrigation system.
The good news is that technology is moving fast, and the cost of high-quality moisture sensors is dropping notably. In addition, an increasing number of sensors now simultaneously measure multiple parameters – for example growing-media moisture, temperature and electrical conductivity – making them an even more potent tool in optimising growing regimes.
So, keep an open mind about both “big data” and “little data”. Both will become increasingly vital in profitable and responsible agriculture.
Dr John Newstead has a BSc in Soils and the Environment and a PhD in Soil Science and Climate Change. Since joining Delta-T Devices nine years ago he has used his expertise and practical experience in the soil sciences arena to help customers plan and execute successful soil moisture and environmental measurement projects.
♦ The WET Centre has been developed by NIAB EMR in collaboration with a number of commercial partners, including CHAP Partner AHDB, CHAP Members Berry Gardens Growers and Delta-T Devices, along with Cocogreen (UK), Netafim UK, and New Leaf Irrigation, and with further support from Meiosis, South East Water, Kent County Council and LEAF.