How an ETH alumnus ended up growing coffee in Zambia

Life on the farm

Farming is not something that runs in Stocker’s family. His father studied physics at ETH Zurich and went on to work as a patent lawyer, and his mother is a doctor. He grew up in Wil near St. Gallen, and many of his summer holidays were spent hiking in the canton of Graubünden. “I’ve always enjoyed being outside, and my interest in farming started from an early age,” he says. His father even made him a child-sized pitchfork so that he could pretend to be a farmer. Once he started secondary school in [1]Immensee, Stocker took any opportunity he could to help out on farms during school holidays, and he soon

began picking up the requisite skills. When his school told him about the ETH degree programme in agricultural sciences, he glimpsed a way of combining his proficiency in mathematics with a passion for working the land. Not long after, an acquaintance offered him an exciting opportunity to go to Zambia on a three-month agricultural assignment. “That’s what sparked my love of Af­rica – and I’ve never looked back!” says Stocker. “I just couldn’t believe how much fertile land was available, especially in a climate in which you can grow crops all year round.” In Switzerland, he was used to a growing period of between five and eight months, depending on the altitude. As chance would have it, another student from his course, Luca Costa, was in Côte d’Ivoire at the same time, picking up work experience on a cocoa and rubber farm. Stocker visited him, and together they began hatching plans for their very own farm.

Learning opportunity in laos

With his Master’s degree in his pocket, Stocker immediately applied for a job as an agronomist with an inter­national coffee producer in Zambia. The company chose a different candidate for the post, but offered Stocker a job in Laos. He agreed and spent two years working as a plantation agronomist in Paksong in the south of the country, planning fertilisation and irrigation schedules, and devising production standards for over 1,200 hectares of coffee. “I was part of a team of agronomists from Asia, Africa, South America and Europe. Professionally, it was a hugely formative and enriching experience,” says Stocker. He scoured the literature for new ideas on how to boost the efficiency of coffee growing in Laos. At the same time, he compiled statistics on how different agricultural practices affect productivity. “The work was directly connected to what I had learned at ETH,” he says.

After two years, Stocker was posted to Tanzania, where his remit also covered the company’s coffee farms in Zambia. Three years previously, he and Luca Costa had found a piece of land in Zambia where they hoped one day to fulfil their dream of running their own coffee farm. “It was love at first sight,” says Stocker. “The land includes a lot of dry forest and part of Mount Sunzu, the highest peak in Zambia. And as someone from Switzerland, that obviously appealed to me!” By 2019, they had raised enough start-up capital to sign a 99-year lease on a 780-hectare plot. The land hadn’t been used for agriculture since the 1990s and was becoming increasingly overgrown. Before they could exploit it, their first task was to build an access road and bridge and lay an eight-kilometre-long, high-voltage power line.

In late 2020, Stocker resigned from his job at the international coffee producer and moved into a dilapidated stone house on the newly acquired land. After renovating the house, he immediately set to work establishing a nursery with 400,000 coffee plants. Right from the start, Mount Sunzu Coffee put its faith in a hybrid variety from a French grower. “It has the typical aroma of indigenous arab­ica coffee from Ethiopia, but it produces higher yields than the original variety,” says Stocker. The hybrid also offers superior resistance against fungal diseases and pests, he explains. To the best of his knowledge, Mount Sunzu Coffee was the first producer to introduce this new variety on a large scale. “It was obviously a risk, but I think we’re going to see some big changes in coffee growing over the next few years as conventional varieties struggle under the pressure of climate change.”

Global knowledge for local farms

Since purchasing the land, Stocker has devoted a portion of each day to optimising the use of resources on his farm, applying all the knowledge gleaned from 14 years of work and study. This expertise is evident in his water management strategy, use of pesticides and fertilisation methods. “By installing a spot irrigation system along the rows of coffee plants, we’ve managed to reduce our water consumption by 30 percent,” says Stocker. The system was developed in Brazil, and Stocker powers it using his own photovoltaic set-up. Nutrients for the plants are added to the water, meaning they can be applied more frequently but in smaller quantities. This increases fertiliser uptake while also reducing nitrogen emissions. Improving sustainability also makes financial sense, says Stocker: his method saves on synthetic pesticides and fertiliser, and also improves the quality of the soil, ultimately leading to higher yields.

Stocker is the only one of the original com­pany founders who lives year-round on the farm in Zambia. Luca Costa, who handles marketing and sales, spends half of his time in Switzerland, while his brother Yanik Costa, the third partner in the business, works full-time from Switzerland overseeing the company’s finances and administration. Stocker is often alone, but there are too many opportunities in his adopted country for him to spend too long feeling homesick. He does admit to occasionally hankering after a good Swiss Alpine cheese, and he misses the chats with colleagues he used to have in his previous job and when he was studying in Zurich. Every now and then, he satisfies that urge by flying to a conference, where he can swap ideas with fellow experts and check out the latest progress in agricultural science.