Harvest SA 85
Beyond the Soil Test: Understanding What Your Crop Needs Throughout the Season
Turning soil, water and plant data into better-informed crop nutrition and irrigation decisions throughout the production cycle
Successful crop production depends on more than applying fertiliser and irrigation according to a fixed programme. What is applied, what remains available around the roots and what is ulti-mately taken up by the plant are not necessarily the same thing. Nutrient requirements also change as a crop develops, meaning that conditions required during vegetative growth can differ from those needed during flowering, fruit set or fruit development.
Traditional soil, water and foliar analyses remain essential tools, but each gives only one part of the picture when interpreted alone. Crop Nutritional Monitoring (CNM) brings these sources together so that soil, irrigation or fertigation water, soil solution and plant tissue can be interpreted as one connected soil-water-plant system.
Traditional soil, water and foliar analyses remain essential tools, but each gives only one part of the picture when interpreted alone.
Patented CNM Methodology and Unique IP
Following Microchem's acquisition by AGQ Labs in 2024, Microchem gained access to AGQ's international agronomy expertise, analytical systems, patented CNM methodology and intellectual property.
The patent protects the use and application of the CNM model, providing a proprietary framework for integrating and interpreting soil, water and plant information to support informed crop-management decisions.
The lysimeter suction probes used within CNM are designed to mimic root uptake. By sampling soil solution at selected depths in the active root zone, they provide measurements that are more rep-resentative of the water and dissolved nutrients available to the crop's roots. Combined with soil, irrigation or fertigation water and foliar results, this gives a much more complete picture of what has been applied, what remains available, what the plant has taken up and where nutrients may have been lost, immobilised or moved beyond the active root zone.
The technology is supported by more than 30 years of historical crop data, agronomic experience and established methodolo-gies across different crops and growing climates. That accumulated knowledge strengthens interpretation and helps identify the most likely cause of a constraint and the management response best suited to the situation.
The strength of CNM lies in interpreting multiple measurements together. Soil analysis shows what is present in the soil. Irrigation and fertigation analysis show what is being supplied. Soil solution analysis shows what is actually available around the roots, while foliar analysis shows what the plant has taken up.
Viewed together, these results help reveal nutrient movement and availability throughout the crop system. The objective is not simply to apply more fertiliser or water, but to understand where the limita-tion occurs and adjust management accordingly.
Monitoring through the crop's phenological stages
CNM is applied throughout the production cycle, with sampling aligned to key phenological stages rather than arbitrary dates. Results from one stage can guide nutrition and irrigation decisions before the next stage begins, allowing management to respond as crop demand changes.
Across the cycle, CNM can be used both to investigate visible production problems and to optimise a healthy crop - supporting yield, fruit size or quality, more efficient nutrient and water use, and lower unnecessary input costs.
Results from one stage can guide nutrition and irrigation decisions before the next stage begins, allowing management to respond as crop demand changes.