“Compared to a large farm field of a single crop, an allotment plot or kitchen garden is a polyculture!”
Also known as intercropping, polyculture is the simultaneous cultivation of multiple diverse crops and animal species. Although this practice makes it more difficult to harvest a specific crop, it increases diversity, improves productivity, and creates a self-sustainable pest-management regime.
Indigenous peoples throughout North America cultivated different varieties of the Three Sisters, adapted to varying local environments. The individual crops and their use in polyculture originated in Mesoamerica, where squash was domesticated first, followed by maize and then beans, over a period of 5,000–6,500 years.
European records from the sixteenth century describe highly productive Indigenous agriculture based on cultivation of the Three Sisters throughout what are now the Eastern United States and Canada, where the crops were used for both food and trade. Geographer Carl O. Sauer described the Three Sisters as "a symbiotic plant complex of North and Central America without an equal elsewhere".
Polyculture offers multiple advantages, including increasing total yield, as multiple crops can be harvested from the same land, along with reduced risk of crop failure. Resources are used more efficiently, requiring less inputs of fertilizers and pesticides, as interplanted crops suppress weeds, and legumes can fix nitrogen. The increased diversity tends to reduce losses from pests and diseases.
Polyculture can yield multiple harvests per year, and can improve the physical, chemical and structural properties of soil, for example as taproots create pores for water and air. Improved soil cover reduces soil drying and erosion. Further, increased diversity of crops can provide people with a healthier diet.
Once established, polyculture is pretty much self-sustainable, but the planning process can be challenging if you want to grow a great variety of crops. Other issues can include things like:
Intercropping requires knowledge of plant families and their needs
Planning process can be complicated
Planting and harvesting processes are more time-consuming
Individual crop yields are often lower than in a monoculture
Thorough research into companion planting is required
