THE CLIMATE KELPIE BLOG: Efficiency essential to business success

Posted by BCG on 28th November 2019

Diversity and efficiency are the two keys to success for Padthaway farmers, Krysteen and Bradley McElroy – diversity to cope with seasonal variability, and efficiency to make the best use of limited resources, both human and water. 

The McElroy’s farm their 840-hectare property in the South Australian Limestone Coast region with their daughter Casey, who is currently enjoying a break to work and study off-farm. Their business includes a diverse range of irrigated enterprises (wine grapes and certified small seed production) and dryland broad acre (cropping, cattle and sheep). This diversity keeps the family busy with no real downtime during the year.

Photo: Bradley and Krysteen McElroy with one of the automated gates that is part of their surge irrigation system.

It was originally a dramatic seasonal drop in the water table that convinced them to invest in improving the water efficiency of their irrigation system, but they have been blown away by the time savings as well. Careful management by the local community, with oversight by the Natural Resources Board, has seen the water table return to an acceptable level.

Irrigation upgrades

“We rely on underground water to drip irrigate our wine grapes and surface irrigate our small seed crops,” said Krysteen. “We had been getting flow rates of 500 kilolitres an hour (kl/hr), but in 2008 this dropped back to a rate of only 160 kl/hr and we realised we needed to make some big changes to our irrigation systems.”

The bays where the small seed crops (lucerne, phalaris and clover) are grown had been flood irrigated, but the McElroys switched over to surge irrigation about 10 years ago. 

With surge irrigation, the gate letting water into the bay is only opened once there is a full head of water. This means that the water moves more quickly across the bay than it does with regular flood irrigation where the gates are left open as the channel fills.

“It was an expensive system to set up, but surge irrigation can water more quickly and with less water and less evaporation than regular flood irrigation.”

Photo: Casey admires a phalaris crop that is almost ready for harvest. Surge irrigation has proven to be a very efficient system for watering their small seed crops.

“It used to take us around 10 hours to water one irrigation bay – so a very inefficient use of water, power and our time,” Krysteen says. “With surge irrigation we can now water one bay in one hour – that’s less pumping time, less time for water to evaporate and as it is fully automated, it really frees up a lot of our time.”

“We recently had a breakdown in this system that reminded us just how time consuming it was to manage everything manually. We used to have to be down there every two hours opening and closing gates. Now we can program the system to manage the watering over the next 12 to 15 hours.

The McElroys have also compacted the base of their channels to reduce seepage.

The water table has now recovered and their flow rate is back to that 500 kl/hr, but there is no way they want to go back to the old system. “Getting our flow rates back up has really improved our confidence in the future of our business,” says Krysteen.

Photo: The small seed crop irrigation bays are roughly 500 metres long, 100 metres wide and have a gradual slope.

Getting the most out of the system

“It’s a very precise system with no waste. We keep full records of every irrigation event, pumping rate, rainfall and anything else that can have an effect on our outcomes. These records are invaluable in informing our future decisions.”

“We’re also increasing our water efficiency with better plant management. We spray to remove perennial plants between the rows of our small seed crops during establishment. Thick grass weeds can really slow down the irrigation water.”

They monitor soil available water at the 30 centimetre depth in the bays using G-Dots (a simple moisture sensor with visual display). “We find them very helpful because you can see how much moisture there is as you drive past. When we’re making decisions about irrigation, we still use a spade to physically check how the soil is holding together and get a good grasp on the soil moisture. But the G-Dots just make it easier to keep an eye on everything.”

Grape vines

Keeping track of the conditions in the wine grapes is even more important.

The McElroys use sophisticated internet-connected monitoring systems in the grape vines to enable measurements of temperature, rainfall and soil moisture at 20 cm, 40 cm and 60 cm to be accessed anytime on the iPad.

Frost is one of their biggest concerns and they have an automated sprinkler system to protect the vines against damage. 

“While these systems make managing the grape vines a lot easier, it is still important that we go out and check the vines ourselves,” says Krysteen.

Photo: The grape vines are on drip irrigation with internet-connected monitoring systems for weather and soil moisture.

“For instance, when there is hot weather, you really need to go and feel how cool the vine leaves are to work out whether there is enough moisture in the system. We need to be well prepared for heatwaves and that means making sure that there is water all the way down to 60 cm so that the vines can withstand the heat.”

“Before the grape harvest we need to dry out the soil profile because stressing the grapes helps to improve the colour and flavour. This is a challenge because if we reduce the moisture level too quickly the berries will split. To overcome this, we use a drip irrigation with a pulse watering method to drive the moisture down the profile. This involves watering continuously for four to five hours, then off for a few hours and then back on for another four to five hours.”

Planning for variability

The McElroys also run dryland broad acre cropping and a sheep and cattle enterprise. They have some flexibility in the area allocated to these two businesses depending on weather and price.

While they do refer to seasonal climate forecasts, they don’t yet feel they are reliable enough to be a major factor in business decisions.

“We are in the high rainfall zone so we will always plant, but spring rainfall is unreliable so we sow early to get the crops up and going in the warm autumn weather. We’re also retaining stubble to maximise soil moisture but snails and slugs are a big problem around here so we need to burn regularly.”

Photo: Bradley uses the iPad to keep monitor conditions in the wine grapes and check the weather apps.

“Other than the unpredictability of spring rainfall, our biggest challenge is spring frost. The grape vines have their sprinkler system, but for the cropping enterprise the most we can do is to grow a range of crops and different varieties to hedge our bets.” 

They use a number of weathers apps for short-term forecasts including the Bureau of Meteorology app (BOMWeather), Elders Weather and AccuWeather. 

“We’re always looking for rain of course, but their main value is in checking for wind and rain ahead of spraying and other farming operations.”

Running such a diversified business does keep the McElroys on their toes, but it’s a challenge they believe is worth it.

“We’re always on the lookout for new ideas and ways to manage the business better,” says Krysteen. “As we have seen with the surge irrigation, even one change can make a huge difference.”

Contact

Krysteen McElroy, 0408 655 108, bkmcelroy22@outlook.com

Catch up on the 2015 interview with Krysteen on the Climate Kelpie website.

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