A total of 17,346 Rooibos seeds are set to travel to the US ahead of a planned mission to the International Space Station (ISS), where they will be exposed to microgravity and space radiation. The experiment will investigate how the uniquely South African plant responds to space conditions, with the seeds expected to return to Earth for further testing in schools.

Source: Supplied From left to right: MaxIQ Space co-founders Bjarke Gotfredsen and Judi Sandrock, US Consulate Cape Town Public Affairs Officer, Sam Werberg and SA Rooibos Council (SARC) seed technician, Cyril Ngqwala with the Nanolab that will carry the Rooibos experiment and other school and university experiments to the ISS.
The Rooibos in Space project reached a new milestone at a farewell hosted by Allison Areias, United States (US) Consul General in Cape Town, for South African school and university science experiments bound for the US. The Rooibos seeds will travel alongside these experiments aboard the same spacecraft.
Weighing approximately 74.2g, the seeds will travel to Voyager Technologies in Texas, where the experiment will be prepared for spaceflight. They are divided into three batches: untreated, scarified, and scarified and treated with a protective agricultural coating.
Secured inside a specialised Nanolab, the experiment will expose the seeds to microgravity and space radiation before they return to Earth for further testing.
Rooibos experiment prepares for ISS launch
A Nanolab is a compact, standardised research module designed to accommodate experiments for spaceflight and the ISS. These modules allow researchers to conduct experiments in space without requiring large, custom-built equipment.
The Rooibos Nanolab is scheduled to travel to the ISS aboard the Cygnus NG-25 commercial resupply spacecraft. The mission is currently expected to launch between December 2026 and January 2027. The revised timing follows changes to the Voyager/NASA flight schedule, including broader adjustments to crew and resupply arrangements, which resulted in the October flight originally allocated to the Rooibos experiment being rescheduled.
“This is an exciting milestone for Rooibos and for South Africans who have followed this project from the beginning,” says Dawie de Villiers, director of the South African Rooibos Council (Sarc). “The scientific objective is to explore what will happen to the Rooibos seeds when they are exposed to conditions beyond Earth, opening up new opportunities to learn more about this uniquely South African plant.”
Testing the seeds after their return to Earth
The seeds are expected to spend four to six weeks in space before returning to Earth. Researchers will then work with schools in the Cederberg region, Rooibos’ natural growing area, and Parklands College to plant the space-exposed seeds alongside control seeds.
Over 18 months, learners and researchers will monitor, measure and analyse differences in germination, growth patterns and plant development as the plants mature.
Learner participation is central to the project, giving young people the opportunity to contribute to a scientific investigation while developing practical science, technology, engineering and mathematics (Stem) skills. The wider Rooibos in Space initiative has also included school engagement, Stem education and a national Mission Patch competition that challenged young people aged 12 to 18 to design a patch for the mission.
Bringing Rooibos seed knowledge into space research
For Cyril Ngqwala, Rooibos seed technician, preparing the experiment has provided an opportunity to combine traditional Rooibos seed knowledge with space science.
“Working with the seeds from preparation through to assembling the Nanolab has been an incredible experience,” says Ngqwala. “We have prepared the seeds in different conditions so that, when they return, we can compare their performance with seeds that have remained on Earth. It’s exciting to think that something as uniquely South African as Rooibos is now part of a space experiment.”
The SARC conceived the Rooibos in Space initiative and developed it in collaboration with MaxIQ Space.
The mission will mark the first time seeds from a South African indigenous plant have been sent into space for this type of research. It will provide an opportunity to investigate how Rooibos, a plant adapted to the Cederberg region, responds to the extreme conditions of space.
Project updates will be shared on the official website, and on social media via @RooibosCouncil on Facebook and @SARooibosCouncil on Instagram.