Meet the Ayocote Medianoche: A Bean That Predates the Aztec Empire

The Aztecs were around from roughly the 13th to the 16th century. The Ayocote bean has been growing in the highlands of central Mexico for somewhere between 4,000 and 6,000 years. So when we say the Medianoche has a history, we mean it predates the Aztec Empire — by a lot.

Named ayocotl in Nahuatl (the language the Aztecs later adopted), these large climbing beans were first cultivated in the Tehuacán Valley, a stretch of highland straddling Puebla and Oaxaca now recognized as a UNESCO World Heritage Site for its role in the origins of Mesoamerican agriculture. They survived colonization, civil war, the French invasion, and a century of industrial agriculture. They are not fragile.

The Medianoche is one specific variety of Ayocote — and it is not like the others.

What Is the Medianoche

Medianoche is Spanish for midnight. We named this bean from a photograph, and the name stuck immediately — the Joel Rivero family and our sourcing partner La Comandanta started using it at markets in Mexico right away.

Look at the photos and you'll understand why. Each handful is a mix of deep black and rich purple beans with a scattering of cream-white — no two handfuls quite the same. It looks like someone scattered stars across a dark sky and called it a bean.

The Medianoche comes from San Pedro Temamatla, a small village in the Sierra Nevada foothills of Puebla, grown by Joel Rivero and his stepfather. The land has been in Joel's wife's family for three generations. Joel and his stepfather learned traditional farming methods from elders in the community, and that is how they still work — no synthetic fertilizers, no chemicals, a horse-drawn plow turning much of the soil, and every step of harvest done by hand by people from the region.

The specific multi-color mix of the Medianoche came about somewhat by chance — a seed experiment that turned out to work extraordinarily well on their particular land. Other farmers have tried to grow it. It hasn't come out the same way. There is something specific to Joel, his stepfather, and that piece of ground in the Sierra Nevada foothills that produces this bean. Nobody has a scientific explanation for it, including them.

The Art of Growing It

After each harvest, the Rivero family lays out the beans and selects next year's seed grain by grain — by color and by quality, done by members of the community. They actively manage the color ratio each season: if black ran heavy, they add more purple and cream into the seed mix for next year. Without this work, the variety would drift toward whichever color dominates, and eventually you'd just have a black bean.

Each plant grows one color. Bees cross-pollinating between plants can cause surprise variations — a seed planted to produce one color sometimes comes up differently. The growers attribute this to bee activity across the field. So even with all that careful selection, nature gets a vote.

The First Time in the US

The Medianoche has been enjoyed in Mexico for generations. It is arriving in the US for the first time through Primary Beans.

We partner with La Comandanta, a Mexican mission-based company working directly with small family farms to rescue ancestral bean varieties at risk of disappearing. By bringing these varieties to US kitchens, we create sustainable income for farmers to continue traditional practices and grow rare beans for generations to come.

We have also placed the name Medianoche in the public domain — permanently. No company, including Primary Beans, can ever trademark it. Any farmer, importer, or small food business working with this variety may use the name freely. Beans that have always belonged to everyone should always belong to everyone.

What to Expect in the Kitchen

The Medianoche is a big, meaty bean with a creamy interior — it holds its shape even through long braises. It is a substantial bean. It has a deeply earthy flavor and an inky black broth that is delicious on its own. It is traditionally enjoyed cooked simply with chilis or in a mole. We also love this meaty gem in a marinated bean salad.

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The Medianoche is not yet available for general sale. Sign up below and we'll let you know the moment it is.

Primary Beans sources rare heirloom bean and grain varieties directly from small family farms, creating the market that makes it possible for farmers to keep growing them. Learn more about our sourcing and our Heirloom Bean + Grain Club.