Balance, in their own words.

DRIS has fundamentally changed how we work with plant nutrition at Cropnuts. Rather than looking at nutrient levels in isolation, DRIS reveals the true physiological status of a crop in a way single-nutrient thresholds never could. This has given our growers a genuinely revolutionary window into plant health and, by extension, the health of the soil microbiome. The full-picture view of nutrition in plant tissues as well as sap enables us to fully evaluate nutrition programmes and crop health.

In practice, this depth of understanding has allowed growers to apply inputs with far greater precision, cutting waste and optimising yield. Additionally, this has materially reduced pest and disease pressure by correcting the underlying imbalances that make crops vulnerable in the first place, reducing reliance on crop protection products and placing plant nutrition at the heart of complete IPM strategies.

Soils under annual cropping in South Africa have been heavily tilled for decades leading to a downward spiral of soil degradation. This spiral starts with soil disturbance due to tillage, then removal of soil surface cover, the loss of soil organic carbon (SOC), loss of nutrients and water storing capacity, runoff and erosion. Between 25 and 75% of the SOC in our crop soils have been lost, leaving us with degraded soils and a reduced production potential. Furthermore, we are losing topsoil from water erosion at a rate of 12 ton/ha/yr. This situation restrains farmers’ productivity, profitability and sustainability. It requires higher levels of production input (especially fertilisers) under increasing financially challenging conditions. The cost squeeze for many farmers has become unbearable and they would rather decide to opt out of farming or are sold out by their financiers.

In this downward spiral, soils are not only biologically and physically degraded, but also chemically. This happens through the loss of nutrients and changing pH, leading to soil nutrient imbalances and excessively low or high pH regimes. We believe that the principles and practices of regenerative conservation agriculture (RA) are the best way to solve this problem and restore degraded soils. However, before we start this restoration and regeneration journey with any farmer, it is necessary to assess and understand their soil’s potential and health status by analysing its physical, biological and chemical status. There are various good analytical methods, but since we’ve needed to get a much better handle on the chemical degradation and nutrient status of soils, we decided to use the DRIS method in our on-farm research trials across the summer rainfall production regions of South Africa. This research is currently funded by The Maize Trust and implemented by ASSET Research.

The DRIS soil and leaf analytical results answered many of the questions and closed many of the gaps we’d had. Some examples are soil compaction and hard setting, weed infestations, nutrient stratification, soil acidity, liming, nutrient imbalances, and poor crop performances. Our experience with the DRIS results, support and recommendations was very positive, particularly from a much deeper understanding of the soil nutrient status and balances. We are realising now that to improve soil health is a fine balancing act, requiring constant monitoring of soil and plant health status, helping farmers and technical advisors to build a solid scientific platform to start or continue their regeneration journey.

I first met Ronald Schroder, senior agronomist at DRIS, in Pongola in 2003. I was farming sugarcane, reading everything I could find on regenerative agriculture, and trying to work out how to bring it to our shareholders without asking them to take the leap of faith alone.

The yields told me conventional practice was failing us. On one 78 ha irrigated block, cane had come off at 130 tc/ha at first cut in 1997 and dropped to 90 tc/ha by the fifth ratoon in 2001, despite 285 kg N/ha going in. We were feeding the crop harder every year and getting less back. If the soil could not sustain yield for longer than six years, the problem was not the soil. It was how we were farming it.

Ronald ran a DRIS analysis on the block. Calcium was low, magnesium high, and the water infiltration problems we had been fighting made sense the moment the ratios were on the page. We put down 2,000 kg/ha calcitic lime and 1,000 kg/ha gypsum, and cut nitrogen from 285 to 170 kg/ha. Yield lifted from 92 tc/ha in 2002 to 102 tc/ha in 2003, the first season after the correction.

My chairman, Mr Freek Naude, backed the change because he could see I was not doing it alone. DRIS put scientific analysis behind every decision. That mattered.

For a while I was the only farmer in the district on this path. When our study group started paying attention to my yields, lower input costs and extended ratoon age, the questions changed. When I brought in the first cane harvester, the eyebrows went up again: the point was to keep the trash on the ground instead of burning it, hold moisture in the soil whilst saving on irrigation costs, and spray Concentrated Molasses Solids (CMS) to help it break down infield. Every one of those decisions traced back to what DRIS had shown us about the soil.

Looking back, it was the best decision I made in my career. The 700 ha farm was eventually sold, a majority-shareholder decision to unlock two generations of family investment, not an agricultural one.

I then spent seven and a half years in Mozambique on a large banana and macadamia enterprise. The owner did not see the case for regenerative methods, to his own detriment. When I returned to Pretoria I moved into R&D in regenerative agriculture. I am now Commercial Manager of Good Agri Solutions (GAS), where we build “prescription blends” for farmers based on DRIS custom recommendations, across a product range from chemical to organic or in combination of both, commonly known as a biological approach.

The turning point in coming back to DRIS was meeting Ronald’s partner, Charles le Roux, and sitting through a full presentation of where the system had moved in just a few years. DRIS is now a complete interpretation and recommendation system, considering soil, water, leaf and sap analysis and finally what ended up in the fruit we produce and sell.

DRIS no longer relies only on Liebig’s law of the minimum. It also works the Mulder’s chart into the diagnosis, which maps the dominance and antagonism patterns between elements, the reason calcium so often ends up being the controlling factor in nutrient balance, rather than one factor among many. It is the only diagnostic system I have seen that addresses soil compaction directly by improving aeration and flocculation, which is what aerobic microbial activity actually depends on. They can even incorporate the farmer’s own waste streams, kraal manure, chicken litter, layer manure, into the recommendation, rather than treating them as afterthoughts. They not only promote the production of biochar and wood vinegar, but their program also calculates the amounts needed on the farmers behalf.

They integrate historical soil records, harvest data and satellite imagery to guide smart sampling, so the sampling points themselves improve over time. And the agronomist portal means any agent can sound like a seasoned agronomist by interacting with the DRIS data and making custom recommendations directly in the system.

The system I trusted in 2003 has become sharper, faster and better at handling the parts of farming that used to sit outside the analysis. That is why DRIS is my agronomy partner of choice.

Any test, trial or chemical or biological intervention is only verified by the crop’s response. Yield and quality. That is where DRIS earns its place, and it is also where most soil and leaf programmes stop short.

I was first introduced to DRIS after the floods of 2000, in sugarcane in the Onderberg region of the lowveld. We wanted to understand what had leached out of the soil and what was now deficient in the plant. The deficiencies we found were not the ones we had gone looking for. DRIS identified sulphur as the most limiting factor, which was not a nutrient we had been prioritising. Once we corrected it, the plants did more than respond to the sulphur. They started self-regulating and redistributing other elements as the balance shifted. That was the point at which I understood the diagnosis was reading something the standard analyses were not.

The work went further. In 2002 we published the DRIS norms for sugarcane in the Mpumalanga Lowveld in the Proceedings of the South African Sugar Technologists’ Association. Building those norms taught me what balance-based diagnostics actually require. Not opinion. Reference standards, validated against field data, tested against the crops they claim to diagnose.

As a soil scientist I spend most of my time on classification work across a wide range of crops. The lens I bring to that work is that a soil has three balances that have to be read together. Chemical, physical, and biological. Addressing those three answers what the soil is capable of. It does not answer how the plant is responding to what is actually available to it. DRIS closes that gap by reading leaf and soil against each other, which shows both how the plant is reacting and which elements have become plant-available. That is the third leg of the diagnostic stool. Until you have it, you are guessing at the last step.

DRIS complements soil testing rather than competing with it, and it fits directly into a zone-based approach to soil mapping, where the cost-saving potential on inputs is significant. On that basis I now bring DRIS into a number of the projects I am working on. We are learning new things together about how creation and nature work with each other.

I have promoted micronised calcium in South African agriculture for more than two decades. It is not a standard agricultural line, and for years it has been difficult to explain to farmers why that matters. Why a micronised, plant-available calcium works differently on soil compaction and aeration than a standard agricultural lime.

Then I was introduced to the DRIS system. What struck me first was that DRIS sees micronised calcium for what it does: its effect on soil compaction, on soil aeration, and on plant-available calcium in the profile. Not just as another line item on a soil test, but as a functional input with a specific physical and chemical role.

DRIS analyses the soil, reads the balance, and specifies the exact kilograms per hectare of micronised calcium required to produce a reaction. The chemical and physical status of the soil are taken into account together. That is a level of specificity I have not seen from any other diagnostic system.

Since we started using DRIS analysis, we have adapted our custom blends to work with the DRIS recommendation. We mix micronised calcium carbonate, gypsum, soft rock phosphate, and available silica according to the specific soil properties DRIS identifies on each farm. The blend is made for that farmer’s soil, not pulled off a shelf.

What matters most is that the loop closes. DRIS lets us test the plant afterwards to see how it has responded to the correction. Whether the calcium made it to the leaf. Whether the balance shifted. Whether the reaction was what we designed for. That is the difference between selling an input and delivering a result.

After twenty years of explaining what micronised calcium can do, I now have a diagnostic system that specifies it before I have to say a word.

DRIS has helped my business stay ahead of our clients’ agronomic needs while simplifying the data and recommendations for the farmer. We had many requests for sap analysis and interpretation. Sap norms are notoriously difficult to establish, but DRIS reads sap through the balance between elements, not against a fixed norm. That filled the gap with confidence.

Sap analysis gave us the ‘what’. The DRIS team gave us the ‘how’. Their targeted recommendations helped us fix imbalances quickly, reduce nutrient waste, and significantly improve yield and quality.