Ocabreeders – Working together to produce a range of hardy, reliable, disease-resistant and high-yield crops for Europe.


The Guild of Oca Breeders

The Guild of Oca Breeders (GOB) is a citizen science plant breeding club that aims to improve the Andean vegetable oca (Oxalis tuberosa) for cultivation in the Northern European growing environment. The more people get involved, the greater our chances of success to achieve our ultimate aim for oca to become as widespread and globally popular as the potato.

Oca is a high-altitude Andean tuber crop native to South America. It’s been grown occasionally in the UK for over 150 years but has yet to become a commercial success. The delicious tubers are short-day plants, which means they only start to form when summer ends and the nights grow longer. Unfortunately, this also leaves them vulnerable to cold and frost and gardeners are discouraged by poor crops.

The mission of the Guild is to breed a variety of oca that responds much better to European variations in day length and climate. Our chosen, proven and simple method is recurrent mass selection: a process by which large numbers of genetically diverse seedlings are planted and the best are selected and replanted the following year. This is the same process through which farmers were able to adapt the potato, originally a short-day tuber itself, to the long-day summers of the northern hemisphere.

Join us!

We are inviting gardeners, scientists and horticulturalists to join us to help grow out and evaluate our new seedling varieties. Your garden will become a test bed for plants that might hold the key to day-neutral, high-yield, disease-resistant varieties of oca. There will also be a chance to take part in experiments to determine the earliest and largest crop performers as well as investigations into best practice for culture.

This is an exciting opportunity to become personally involved with global food security and to make a valuable contribution to the future diversity of food cultivation. Read more about what our members do or sign up for updates and more information.

Please note that all of our tubers are released under the Open Source Seed Initiative (OSSI) pledge, so taking part in the project means you commit to keeping the germplasm in the public domain.

No time for science but love oca?

If you’re interested in oca and would like to have a go at growing, one great way to support us is to buy your oca tubers from us. Our varieties are all unique and carefully selected from our best performers to date.

More ways to help…

The Guild of Oca Breeders is a self-funded project wholly sustained by members and volunteers. If you’d like to get involved and offer your support, please do get in touch. We’re particularly keen to hear from anyone with technical and marketing skills.

We’re also actively seeking grant and investment funding.

And if you have suggestions and ideas, let us know!