PlantSap® – A South African Innovation in Crop Nutrition

Though initially disappointed, he took this as an opportunity to create something tailored to local conditions. He assembled a team of experts and advisors, funding the research entirely on his own. The development and validation of the system took nearly four years, culminating in the registration of the PlantSap® trademark and concept in 2021.

Jan Hendrik Petrus van der Merwe, founder of PlantSap®, has always had farming in his blood. Growing up on a farm in Bospoort in the North West Province, his path in agriculture began early. After completing four years of agricultural studies in Pretoria—majoring in Agronomy and Soil Science—he added a Finance Management course through UNISA and later completed specialised training in soil microbiology and microscopy through the ARC and Rhodes University.

In 1989 Jan returned to the family farm where he farmed until 2001. Following the sale of the farm, he relocated to Pretoria and began working as an agricultural consultant for local and international companies. During this time, he also ran a part-time flying school, but his focus remained on agriculture. From 2003 to 2015, he served as a technical marketing manager, training agents and transferring agronomic knowledge to assist farmers.

In 2012, he launched a personal research project to distinguish between actively growing and dormant plants. This challenge inspired a deeper dive into the science of plant health. By 2015, Jan made the bold decision to pursue the development of what would become the PlantSap® technique.

In 2016, he dedicated an entire year to monitoring crops daily—measuring plant sap, recording data, and analysing results. The process revealed compelling insights. Eager to expand his understanding, he travelled to the Netherlands, a global hub of plant sap analysis expertise. There, he spent a month working closely with leading consultants, applying the methods practically on farms. However, without access to licences or IP from their system, Jan returned home determined to build a unique South African solution.

Since then, PlantSap® has grown steadily, with the method now implemented at several large, high-performance farming operations across the country. To support scalability, custom software was developed to handle data processing and management—allowing the system to be easily adopted by more farmers and agronomists.

A Regenerative Recipe for Farming Success

At its core, the PlantSap® system and the specific measurements enables regenerative agriculture—also known as “farming with nature.” Until recently, this approach lacked a practical implementation method. PlantSap® filled that gap by developing a science-based, replicable system that helps farmers make real-time decisions to support plant health and performance.

What sets PlantSap® apart is its dual-focus approach. The consultant/agronomist combines soil health with plant sap insights to create a complete picture of the soil-plant relationship. By doing so, it empowers farmers to make precise, informed corrections based on what the plant is actually absorbing.

Another major breakthrough has been PlantSap®’s method of expressing plant sap from leaves, especially from tree crops. Traditional techniques struggled with woody plants, but the company’s innovative approach proved so effective that it gained recognition internationally and helped expand their global research database.

From Concept to Commercial Success

The journey from idea to commercial launch took about five years, followed by another five years to refine what Jan calls the “regenerative recipe.” The biggest hurdle was funding—PlantSap® was entirely self-financed. Every phase of growth required reinvestment into research and development.

Still, the passion for results kept the team motivated. The first major success came when the method was commercialised, and immediate improvements were seen in yield, quality, and farmer satisfaction. The evidence was undeniable.

Despite initial scepticism from the broader agricultural industry and academic institutions, PlantSap® continued to thrive. “We no longer need to convince anybody—the results speak for themselves, and farmers are our best advocates,” Jan explains.

Looking to the Future

With a decade behind it, PlantSap® is now positioned to become a standard part of crop monitoring in South Africa. The goal for the next five to ten years is to see the system widely adopted, enabling more farmers to grow healthier crops while reducing chemical inputs and environmental impact.

The company’s partnerships with digital platforms like FieldView and the use of NDVI technology have further enhanced its capabilities. By integrating digital monitoring with plant sap analysis, PlantSap® gives farmers a full-spectrum view of their crop health.

Science, Speed, and Sustainability

PlantSap® prides itself on delivering fast, research-backed results. Test outcomes are returned to advisors within five working days, allowing quick, targeted intervention. The company also builds on foundational work by respected South African scientists like the late Dr Arrie Jansen van Vuuren and Professor Hannes van Staden.

The entire PlantSap® technology was build doing statistical trials and underwritten by specialists in there field.

A Lasting Impact

Today, PlantSap® is recognised globally as a leader in real-time plant nutrition analysis. The method continues to evolve, becoming more accurate each season. Its benefits are clear: early detection of nutrient imbalances, improved fertiliser efficiency, increased yields, and stronger, more resilient crops.

As Jan reflects on the journey, he remains inspired by the impact: “We’re doing something different. Talking with Plants is our business”