Sustainable Agroecological Practices in Milpa Systems

The milpa system is a traditional Mesoamerican agroecosystem built on the intercropping of maize, beans and squash, often enriched with secondary species such as chilli, amaranth or fruit trees. This polyculture harnesses ecological interactions—nitrogen fixation by legumes, soil cover by broad-leaf species and pest regulation through diverse plant assemblages—to maintain soil fertility and suppress weeds without reliance on synthetic inputs. Agroecological practices within milpas include slash-and-mulch to retain organic matter, rotation of cropping cycles to break pest and disease cycles, incorporation of cover plants for continuous soil protection and nutrient cycling, and participative seed-saving to preserve local varieties. Such practices enhance on-farm biodiversity, boost nutrient density of harvests and bolster resilience to climatic variability through microclimate moderation and improved water retention. Despite its proven benefits for food security, nutritional self-sufficiency and carbon sequestration, the milpa faces pressures from labour intensity, market forces favouring monocultures and land tenure constraints. Current research emphasises adaptation of ancestral knowledge to contemporary challenges, with tailored milpa designs extending beyond Mesoamerica to inform sustainable agriculture globally.

Research from Nature Portfolio

Quantitative analysis of nearly a thousand farm households in the Western Highlands of Guatemala has revealed that more than two-thirds of plots under milpa management deliver higher total energy yields and supply a broader spectrum of essential nutrients than monocropped maize. By calculating a Potential Nutrient Adequacy indicator across diverse intercrop combinations, researchers demonstrated that maize–bean–potato and maize–bean–faba intercropping achieved the highest micronutrient provision, outperforming monocultures in meeting recommended dietary allowances. The study underscores the importance of maintaining or reintroducing locally adapted intercrop mixtures to improve nutritional security and supports the development of region-specific milpa models tailored to distinct agroecological settings.

Sustainable Agroecological Practices in Milpa Systems publication trend

The graph below shows the total number of articles in sustainable agroecological practices in milpa systems across all publications each year (not limited to Nature Index journals).

Technical terms

Milpa system: A traditional Mesoamerican polyculture combining maize, beans and squash, often with other species, to exploit complementary ecological functions.

Polyculture: Cultivation of multiple crop species simultaneously in the same field to enhance resource use efficiency and biodiversity.

Intercropping: Deliberate planting of two or more crops in proximity to promote positive interactions such as nutrient sharing or pest suppression.

Slash-and-mulch: Agroecological practice of cutting vegetation and distributing it over soil surface as organic mulch to conserve moisture and soil organic matter.

Potential Nutrient Adequacy (PNA): An index measuring the capacity of a cropping system to deliver recommended daily intakes of essential nutrients per unit area.

References

1. Review of agronomic research on the milpa, the traditional polyculture system of Mesoamerica. Frontiers in Agronomy (2023).
2. Maize intercropping in the milpa system. Diversity, extent and importance for nutritional security in the Western Highlands of Guatemala. Scientific Reports (2021).
3. Exploring nutrient-sensitive landscape configurations for rural communities in southern Mexico. Landscape and Urban Planning (2024).
4. Reuniting the Three Sisters: collaborative science with Native growers to improve soil and community health. Agriculture and Human Values (2022).