Soil Wealth investment reaps benefits

Helping growers adjust their on-farm practices to improve their productivity, profitability and competitiveness was at the heart of the Soil Wealth and Integrated Crop Protection – Phase 2 (VG16078) program.

Delivered from 2017 to February 2023, the Soil Wealth and Integrated Crop Protection program was targeted at vegetable and potato growers and led to lasting soil and crop health improvements gains, achieved by growers applying the latest information and innovations and remaining adaptive to current issues.

Feedback has shown 75 per cent of participating growers had or were intending to change their practices to improve soil health and/or crop protection on their farm.

Here, we showcase how two project demonstration sites are displaying tangible results.

Reducing tillage and improving soil health with Mulgowie Farming Company

Mulgowie Farming Company is an Australian owned and operated vegetable grower and packer with operations in East Gippsland in Victoria, northern Queensland, Lockyer Valley in south-east Queensland and northern New South Wales. The enterprise grows conventional and organic sweetcorn, green beans and broccoli.

Mulgowie Farming Company founder, Rodney Emerick, started his team on a path to improving soil health through the adoption of controlled traffic farming. Andrew Johanson, Mulgowie’s sustainable agriculture manager, saw a successful Soil Wealth Integrated Crop Protection (ICP) strip tillage demonstration in 2018, which piqued his interest. This led Andrew and his team to investigate expanding practices such as strip tillage and cover cropping to more of their growing regions.

In 2019 and 2020, Mulgowie in collaboration with Soil Wealth ICP trialled strip tillage combined with existing cover cropping practices at its Maffra farm, 220 kms east of Melbourne.

The primary goal was to use strip tillage to improve soil health characteristics such as water infiltration and water holding capacity, to increase crop health and yield, reduce costs and ultimately improve profitability.

“For me, seeing was believing,” Former farm manager Michael Evans said. “Despite my original scepticism, after half an hour of trying strip tillage in different cover crop scenarios at the Maffra site, we were quite blown away by how it could convert the cover crop to an area ready for planting vegetables.”

“We purchased the machine on the spot, and the trial went from a few hectares to being adopted across the 200 hectares destined for growing corn.

“After using strip tillage, the corn crop was the most even I have ever seen it in my 17 years of farming, despite the gullies through the paddock and uneven beds. We saved costs on in-crop herbicides, fuel and labour hours.”

KEY BENEFITS OBSERVED FROM STRIP TILLAGE AT MULGOWIE

• Improved soil structure – more friable, less compacted, less dispersion of soil particles
• Better soil water infiltration and water holding capacity
• More soil and crop resistance to extreme weather events
• Improved crop uniformity
• A 0.5 per cent over three year increase in soil carbon, following adoption of strip tillage
• Lower labour costs
• Reduced fuel costs
• Less weed pressure and subsequently the cost of in‑crop herbicides
• Reduced nutrient use – nitrogen and phosphorus
• A 26 per cent increase in bean yields, and maintained corn yields between conventional and strip tillage

Healthy soils, healthy profit from precision ag trial at Koo Wee Rup

In 2018, a trial was developed at the Soil Wealth ICP demonstration site at a farm about 80km south-east of Melbourne, Victoria. The partnership, including Schreurs & Sons and Stuart Grigg Ag-Hort Consulting explored the application of precision agriculture (PA) in celery, leek and baby leaf production systems on Adam Schreurs’ Cora Lynn Farm.

Like many intensive Australian vegetable production systems, Adam has challenges with soil management, crop health and variability, and weeds while continuing to supply customers with high quality produce year-round. This can be compounded by poor drainage and waterlogged soils, nutrition constraints and insect pest damage depending on the seasonal conditions. Adam sees on-farm research and innovation as key to addressing these challenges and continually improving management practices.

“The demo site provided the opportunity for us to look right into it, see what we could do, and measure some of the differences,” he said.

Over the past five years Adam and the team have aimed to improve nutrition, irrigation and drainage management, and insect pest and beneficial monitoring as a basis for soil and crop health. To achieve this, PA technologies were used including EM38 mapping, gridded soil sampling, variable rate fertiliser spreading, remote weather stations with soil moisture probes, automatic insect pest traps with cameras, microwave weeding prototypes, as well as drones.

Adam highlighted the importance of starting small and then scaling up when seeing productivity benefits from on-farm trials in a commercial setting.

“Through gridded soil sampling and variable rate lime and fertiliser (application) we’ve been able to even everything up correctly,” he said. After doing this for a couple of years the crop was much more uniform and yields were increasing. I did a little bit more on the property, and then a little bit more. We’re now using the system from the trial plots right across the board (at other farms) with very good results.”

Adam will continue to refine and expand the use of PA technology across other farms to continually improve yield and crop uniformity.

“It is a really good demo of what technology can be used in the field and what we can get out of it. All of those things I will be using in the future, more and more.”

KEY BENEFITS FROM THE PRECISION AGRICULTURE TRIAL

• Celery yield assessments showed higher average celery heart weights and more uniformity across the trial block from 2018-2020. Average leek yield increased in the trial area compared to the control from 2020-2022, with a significant increase in minimum yield.
  
  
• Soil health has improved in the trial area when looking at soil fertility indicators, nutrient status, plant nutrient availability and free-living nematodes.
  
  
• There has been a reduction in soil-borne disease risk and severity over time at the site, which has been more pronounced in the trial area compared to the control.
  
  
• Improved yield and crop uniformity contributed to an increased gross profitability of $53,000, or $5000 per hectare, largely driven by reduced costs from post-harvest labour efficiencies in cleaning, grading and packing produce.

What is next for Soil Wealth?

After the success of the first two phases of the Soil Wealth and Integrated Crop Protection program, Hort Innovation recently contracted a third phase with Applied Horticultural Research (AHR) and RM Consulting Group (RMCG). The Australian melon industry will also join the new phase of the program so melon growers can learn how to improve soil health, crop health, and reduce costs.

The consultation process and grower focused co-design workshop identified the following themes for the new program:

1. Soil health, which underpins sustainable farming systems and the production of healthy crops. Improving soil management practices will help vegetable growers gain a more productive and resilient natural resource base with a focus on soil care, increasing organic material and improving grower margins.|
   
   
2. Crop health, driven by improved soil health and crop protection measures. Improving crop protection management practices will help vegetable growers produce healthier and more profitable crops through managing insects, diseases and weeds to maintain healthy plants.
   
   
3. Optimising inputs for healthy soils and crops, and profitable vegetable businesses. Increasing skills in the effective use of nutrients, water, chemicals and other resources (e.g. plastic to minimise waste) will help vegetable growers to maintain market advantage and demonstrate sustainability.
   
   
4. Carbon and climate, mindful that climate influences what, when and how soil and crop health can be managed, including associated input use. Increasing awareness of changes in climate, both in extremes and longer-term averages, will be important for adapting production systems. Understanding the role of carbon will help vegetable growers to remain profitable and sustainable into the future.