The Ancient Inca had population centres from the arid Pacific Coast to the high elevations of the Andes and all the way down to the tropical rainforest’s of the Amazon Basin. With such diverse landscapes and climates, the Inca employed many different agricultural techniques to grow a wide variety of crops. Amongst these communities was a network of trade and food storage that kept everyone food secure.
The most celebrated of the Incan/Andean farming techniques are the terraced slopes of the Andes mountains. Machu Picchu is world renowned for its beautiful architecture and pristine surroundings, and incorporated within in its design were agricultural terraces and accompanying water harvesting canals that supported up to a thousand residents. Recently, people have been revisiting these techniques of old for a look at what a more sustainable future might be.
Growing What Grows
Elevation hugely influenced Incan agriculture. The altitude determined what staple crop would be grown. Along the coast, the Incan diet was based around seafood and fruits. In the Andes, maize was cultivated on the lower slopes (below 3200 meters), and quinoa at elevations between 2300 and 3900 meters, with maca crops going even higher than that. Cotton and coca were cultivated at around 1500 meters and under. Tomatoes, chili peppers, and peanuts were also part of the annual garden system. In the Amazonian lowlands, tubers like cassava, oca, sweet potatoes, and mashua were the stomach-fillers.
Potatoes, however, were the main staple, grown between 1000 meters and 3900 meters in elevation. Peru now has thousands of varieties. Chuño was (and remains) a popular way to prepare/preserve potatoes. In this case, potatoes were naturally freeze-dried by putting them through a natural sequence of freezing and thawing brought on by the cold days in the Andes and the frost-bitten nights. This preparation gave the potatoes a long shelf-life (we’ll get into preservation in a minute), and chuño was typically rehydrated to add to soups and stews for consumption.
Spaced out amongst these annual and perennial staple crops were a collection of fruit trees and vines, as well as some domesticated animals. Avocados, cherimoya, and passionfruit grew on the slopes of the mountains., as did papayas, prickly pears, lulo/naranjillo, and Cape gooseberry. Bananas were around on the lower slopes, as were an assortment of berries. As for meat, it was eaten in small quantities, with the native and domesticated guinea pig being the main source. Camelid meat was also eaten, but llamas and alpacas were mostly used as beasts of burden and sources of wool.
Due to high elevation, steep slopes, and wet-dry seasons, the Andes Mountains required some finesse when it came to cultivation. The Incan solution was huge, dry terraces. This flattened the land out so that it was workable. The contents of the terraces were held in place by stone walls, and the terrace walls could be anywhere from two to five meters tall. These stone walls prevented the soil from eroding as well as provided a warming effect (via thermal mass) at the root level at night. The terraces had a layer of topsoil but were filled with a mix of soil and gravel, which allowed water to infiltrate while not becoming so waterlogged that the terrace walls burst.
Due to high amounts of rain, water management was a huge part of the terrace system, and the Incas were experts at it. The terraces, built below the city to prevent mudslides, caught, pacified, and absorbed the water during rainy season. For dry season or drier regions, the Inca built aqueducts with channels, both above and below ground, to transport water from the melting glaciers to the agricultural fields, and they also built cisterns for further storage. The aqueducts are still in use today and have reliably provided water in times of drought.
Around Lake Titicaca, betwixt modern-day Peru and Bolivia, waru-waru systems—raised beds with canals between them (like the Aztec Chinampas in Mexico)— were commonly used, but may have been out of commission already by the time conquistadors came and ruined it all for the Inca.
An interesting variation on this terrace system is a site called Moray. Here, rather than terracing mountain slopes, terraces were formed in craters, going lower with each level. This created microclimates, with temperatures varying as much as 15 degrees Celsius between the top and bottom levels. Only here, the temperature dips as the elevation decreases. Amazingly, the centre, all the way at the bottom, drains so well that it never floods. The site remains somewhat mysterious, but most believe it was used an agricultural research centre to help with determining what could/should be grown where.
The Inca were, perhaps, amongst the world’s best “preppers”. They were meticulous about stowing away food for leaner times. They built storehouses (qullqa) throughout the empire, and state officials kept close track of what was in storage. Maize, potatoes, and quinoa were the most commonly stored foods, and the Inca employed techniques that could make them last several years in one of these storehouses.
Qullqa were relatively formulaic, usually round for corn and square for roots, and designed so as to utilise natural advantages. They were built into hillsides to take advantage of cool breezes, which were let in via channels in the floor and allowed out through openings beneath the roof. They also had drainage that allowed water to leave should rain be an issue. They were generally at lower elevation to avoid frost, and collections were spaced about a day’s journey away from one another. Smaller qullqas could hold about three-and-a-half cubic meters of food while larger ones handle about five-and-a-half.
Chuño was the number one storage crop, and under these conditions, it could keep for up to four years. Other root vegetables were stored in layers of straw. Quinoa and corn were shelled and stored in jars, and beans and seeds were in the mix as well. Ch’arki, a jerky made from llama or alpaca meat, was a luxury item kept for special occasions and collected as a state tax. While this food was partly used for feeding the military, it was very much an insurance policy for years with weak harvests.
The Cycle of Knowledge
An assortment of other goods, from armor to wool to wood, were also stored in qullqa, the Inca always acknowledge that conditions in the Andes were unpredictable. Climate change is proving that the world at large is no different, and undoubtedly, revisiting techniques like those of the Incas (and the similar rice terraces of East Asia) as well as other ancient cultures can remind us all that petroleum-based agriculture, the frozen food section, and international shipping are but blimps on the radar in terms of producing, storing, and distributing food.
As modern minds move towards more sustainable means of survival, we can carry with us the folksy wisdom of past generations and use the advantages of appropriate technology from today’s tool chest. The homogenized Western food system—the “Green” Revolution—has failed to feed the world as promised and has, in fact, put the globe and our global community at great jeopardy. The opportunity to change this narrative is growing smaller by the day, and a new restorative revolution will be necessary to dig us out of the deeply plowed ruts of the last few decades.
Looking seriously back at ancient history—a time when local resources, landscapes, and climates had to be respected—to find the way forward provides us with better routes to benefitting both people and the planet. For those in mountainous regions, the Andes (and the Inca) may be a great place to start.