Patricia Seaba faced many challenges when she began farming, but one issue that perplexed her the most was the exploding cabbages. One moment, the plants appeared healthy, growing into beautiful purple and white heads. Then, suddenly, she would hear a pop from the field, and upon inspection, she would find that some of her cabbages had burst open like balloons. This strange phenomenon continued throughout the growing season, and while not every cabbage had this issue, enough did to make it a significant problem. Seaba, puzzled by the situation, knew the plants were trying to communicate something, but she didn’t understand what they needed.
The solution came in 2023 when a government liaison visited Seaba’s farm with a small device that could measure the moisture content in the soil. The device, known as the Chameleon, had been developed by the Virtual Irrigation Academy (VIA) to help farmers measure soil moisture with precision and improve irrigation practices. Seaba and her partner, Rinae Tshikangavhadzi, were initially skeptical, but they decided to give the device a try. It quickly revealed that they had been overwatering their crops, and this was the cause of the exploding cabbages. The plants were drowning from too much water.
VIA’s founder, Richard Stirzaker, had long been dedicated to solving the problem of efficient water use in agriculture. Having grown up in Cape Town, Stirzaker’s childhood fascination with plants and their growth led him to study soil physics and work with smallholder farmers in sub-Saharan Africa. He noticed a common issue: small-scale farmers had limited access to technology that could accurately measure soil moisture, unlike large commercial farms. As a result, farmers often relied on visual cues, which were not always reliable.
For smallholder farmers, irrigation is often a guessing game, leading them to either overwater or underwater their crops. Overwatering, in particular, can have harmful effects on soil health and crop yield, draining resources and increasing costs. Stirzaker realized that there needed to be a simple, affordable, and effective solution for small-scale farmers to manage their water use more precisely.
The Chameleon and the Wetting Front Detector (WFD), another invention by Stirzaker, provide exactly that. The WFD measures how deep water penetrates the soil and whether it reaches the plant’s roots, while the Chameleon measures the suction power of the soil, indicating how difficult it is for plant roots to extract water. These devices are affordable and user-friendly, with the Chameleon using a simple color code—red for dry soil, green for moist, and blue for wet—making it easy for farmers to interpret the data.
The devices have had a significant impact on Seaba and Tshikangavhadzi’s farm. Before using the Chameleon, they irrigated their crops three times a day, just as other farmers in the area did. This method led to high electricity bills, as they had to run a pump continuously to move water from a nearby dam. After adopting the Chameleon sensors, they were able to optimize their irrigation practices, reducing water waste and saving money.
VIA’s mission is to help smallholder farmers like Seaba and Tshikangavhadzi by providing tools that enable them to make informed decisions about their irrigation practices. Today, VIA produces most of its devices locally in South Africa, and they have expanded to Malawi, where they’ve set up a second production line. The organization has sold nearly 100,000 WFDs and Chameleons in 20 countries, reaching small-scale farmers through NGOs and projects.
For Seaba and Tshikangavhadzi, the use of the Chameleon sensors not only improved their farm’s water management but also helped them achieve an international quality and sustainability certification, the Global G.A.P. This certification was crucial for accessing larger markets, and the devices provided a straightforward way to demonstrate their responsible water usage. As they celebrated their achievement, they knew that the real success was in how much their farm had grown and improved, thanks in part to the precision that the Chameleon sensors provided.
