Ancient Tribe’s ‘Floating Farms’ Were Way Ahead Of Their Time
Unfortunately mention of the Aztecs is all too likely to make us think of human sacrifice, but that does a grave injustice to this ancient civilization. There’s much more to the story of the Aztecs than their well-attested sacrificial rites. Take agriculture: it turns out that hundreds of years ago the Aztecs perfected one of the most efficient crop-growing methods history has ever seen. And people studying this today are realizing that there are lessons to be learned from the Aztec ways.
Aztec origins
To better understand how the Aztecs came to develop their astonishingly productive and ecologically sound agricultural system, let’s find out a little more about this lost Central American civilization. The origins of the Aztecs are not entirely clear.
But historians believe that they probably migrated from a place called Aztlán in what is now north-west Mexico, moving southwards into central Mexico. The name Aztec is derived from Aztlán, a place whose precise location has been lost to history.
An eagle, a cactus, and a snake
Some researchers think that the chaos that followed the collapse of an earlier civilization, the Toltecs, may have triggered this migration south. Aztec legend had it that they made this move at the demand of their god Huitzilopochtli.
Huitzilopochtli told the Aztecs, or the Mexica as they called themselves, to look out for a special sign as they migrated. They were to hunt for a cactus with a giant eagle perched on it: the bird would be eating a snake
Tenochtitlan
Improbable as it might seem, Aztec lore records that they did indeed come across an eagle, a cactus, and a snake: cynics among you might suggest the stories were adapted afterwards to fit the facts! In any case, they chose this spot, Lake Texcoco, to settle; in around 1325 they founded what would become the great city of Tenochtitlan on the site of modern-day Mexico City.
But the land there was starkly different in its geography 800 years ago compared to now: the terrain consisted of five interconnected lakes. This waterlogged land was to present the Aztecs with some difficult challenges.
Not enough land
At first the Aztecs only occupied a couple of small islands in Lake Texcoco. That was fine during the initial phase of settlement but as the Aztec population grew, so new problems emerged. The principal headache was the amount of land available in this marshy environment.
There just wasn’t enough of it: there were just the five large lakes dotted with marshy islands. And one of the major problems arising from this dearth of dry land was agricultural in nature.
Radical change
This shortage of agricultural land, and their resulting inability to grow enough food, became more acute as time passed. At the start, the Aztecs had been just one of the many small city-states that existed in Mesoamerica.
In fact the top dogs in the region were the Tepanec and the Aztecs were obliged to pay tribute to their overlords. But in 1428 the geopolitics of the region were about to change radically.
Aztec Triple Alliance
It was in that year that the Aztecs entered an alliance with two other city-states, Tlacopan and Texcoco. This grouping is known by historians as the Aztec Triple Alliance and it was powerful enough to overthrow the dominance of the Tepanec in battle.
The Aztecs were now the primary power in the region, and they were able to extract tributes from other city-states. And naturally enough, this new-found status also heralded a rapid growth in population.
Food production problems
The Aztecs’ problems of food production and space for building became increasingly pressing. To begin with, land needs in the center of Tenochtitlan were solved by building bridges and wooden walkways between the different islands.
But that still left the problem of food production. And the solution the Aztecs arrived at is a real testament to their ingenuity: they found an incredibly effective way to grow crops on waterlogged land, and even in lakes.
Chinampas
The Aztecs cleverly surrounded the center of their city with strips of artifically-created land called chinampas. These small agricultural patches were raised above the waters, and they proved highly productive.
Their extraordinary productivity came from the sediment below the lake waters which was incredibly fertile. But to exploit this soil’s useful feature, they had to build small islands. And it’s the way they did this that was so smart
No easy feat
So how did the Aztecs construct these chinampas? As Wu Mungren, writing for the Ancient Origins website, points out, “Turning a swamp into farmland was no easy feat.” But it was a task to which the ingenuity of the Aztecs was equal.
In fact this technique had likely been used by other peoples of Mesoamerica before the Aztecs adopted it. But it was they who elevated this method to its most sophisticated heights.
Islets anchored to the lake bed
A chinampa was basically an islet anchored to the bed of a lake or swamp. The first step in constructing one was to mark out part of the lake with wooden stakes into a rectangle roughly 100 feet long and about 8 feet wide.
The builders would then fashion a wall between the stakes using wattle, a latticework of branches and reeds. The farmers then filled the resulting enclosure with mud from the swampy lake bed, rotting vegetation and other organic material until the mixture sat above the lake’s water level.
Willow trees
Part of the genius of the chinampas was that the stakes used to construct the small island were actually a kind of willow tree, the ahuejote. In time these tree stakes would take root, securing the chinampas in place and growing into trees that would provide shade and wildlife habitats.
Writing for the BBC, Soumya Gayatri tells us that these natural fences would also “prevent erosion, protect the chinampa against wind and pests, and act as natural trellises for vine crops.”
Seven different crops
Gayatri goes on to point out that in their heyday the chinampas could support seven different crops in the course of a single year. This meant that their productivity could be an astonishing 13 times higher than agriculture on dry land.
At their height, the chinampas covered an area of some 5 square miles, more than 3,000 acres. What’s more, their produce was supporting a population of around 250,000.
A network of canals
But there was more to these floating fields than initially met the eye: they were crisscrossed by a network of canals which the Aztecs could easily navigate by boat or canoe.
These waterways also acted as a highly efficient irrigation system. The chinampas could absorb all the water they needed from the canals. Heavy seasonal rain could lead to flooding, so the Aztecs built a water-management system that included dams and sluices to control the flow.
Healthier and more fragrant
The Aztecs also increased the fertility of their chinampas with the use of natural fertilizer. Their chosen method of doing this was to use human waste. Now, that might sound fairly unpleasant to modern ears.
But it was this aspect of the chinampa system that helped to make it highly sustainable. In fact, since human waste was collected from the city for use on the chinampas, this also made Tenochtitlan a healthier and no doubt more fragrant place.
A wide range of crops
The wide range of crops that could be grown on the chinampas included everything from chilies and beans to squashes and maize, not to mention leafy vegetables. Cultivators also grew beds of flowers which were important to the Aztecs for their sacred ceremonies.
The new natural habitat created by these canals and fertile chinampas also created excellent conditions for fish and wildfowl. And in turn, this wildlife became a further valuable food source.
Spanish conquistadors
The Aztecs had developed a highly efficient system of agriculture by using the resources available around their great city of Tenochtitlan. It was a farming method that ensured there was ample food to feed their growing population.
But in the 16th century, events would take a turn that would ultimately all but destroy the great civilization that the Aztecs had built. The Spanish conquistadors arrived in Mexico. Among them, Hernán Cortés is the most famous — or infamous.
A source of trouble
Cortés was born in the Spanish region of Castile in 1485. He seems to have been a high-achieving youth with one of his contemporaries describing him as “very intelligent and clever in everything he did,” according to Britannica.
But the same source claimed that he was “a source of trouble to his parents.” The adventurer would certainly go on to be a source of trouble to the Aztecs, to put it mildly.
Bound for the Yucatan
Cortés left his native Spain in 1504 and spent the following years in Hispaniola — the Caribbean island now divided into Haiti and the Dominican Republic — and Cuba. It was in February 1519 that Cortés set off from Cuba bound for the Yucatan, in what is now Mexico.
His expedition included 11 ships with about 100 sailors, 500 soldiers, and 16 horses. The impact that this relatively small party would have on the Aztecs would in time be devastating.
No way back
First landing at Tabasco, Cortés then sailed further along the coast to a spot where he founded the city of Veracruz. There, he showed his determination to succeed in conquering Mexico for the Spanish crown by sinking all of his ships.
There was now no way back: after trekking with his forces across the Mexican interior, Cortés reached Tenochtitlan in November 1519. The Aztec king, Montezuma, welcomed this strange outsider “with great honor,” Britannica tells us.
Deteriorating relations
But relations between the Aztecs and the Spanish soon deteriorated. Cortés put Montezuma under house arrest and things worsened when in 1520 he died, perhaps at the hands of the conquistadors.
Unsurprisingly, the Aztecs now expelled the Spanish from Tenochtitlan. But Cortés soon returned, now strengthened by a force of as many as 200,000 indigenous people from various city-states who were disenchanted with Aztec rule.
Weakened by smallpox
Cortés’ army now besieged Tenochtitlan, with the operation extending for 93 days into August 1521. Weakened by the smallpox that the Spanish had unwittingly introduced to the city, the people of Tenochtitlan finally surrendered.
This was effectively the end of the Aztec empire. What it also meant was the end of the chinampas farming system. This ingenious agricultural technology would not survive the demise of Tenochtitlan, which would be replaced by Mexico City.
A letter to the Spanish King
When Cortés had first arrived in Tenochtitlan, he had greatly admired the choice of foods on sale in the markets. What he saw was, of course, the produce that had been provided by the chinampa system.
In a letter to the Spanish King, Cortés described what he’d found. “There are all kinds of green vegetables, especially onions, leeks, garlic, water cresses, nasturtium, borage, sorrel, artichokes, and golden thistle; fruits also of numerous descriptions.”
A fragment of the chinampas system
Yet despite his admiration for this abundance, by conquering the Aztecs and taking their great city, Cortés was responsible for the rapid decline of the chinampas. The Spanish destroyed many of the dams and sluices that maintained the artificial islands.
Instead, they began to drain the land for more orthodox agriculture. In fact, though, the chinampa system has not been entirely lost to history. Despite the urban sprawl of Mexican City, a fragment of the chinampas still exists to this day.
A World Heritage Site
In her 2022 BBC piece, Gayatri described a visit to the Floating Gardens of Xochimilco, which lie some 20 miles outside Mexico City. And as she makes clear, she’s far from alone on her trip.
As she tells us, “The endless maze of canals and waterways was already filling up with colorful trajineras (flat-bottomed boats) packed with day-trippers from the Mexican capital”. This small surviving example of chinampa farming at Xochimilco has become a tourist attraction and indeed it’s a World Heritage Site.
The axolotl salamander
As Gayatri puts it, “The World Heritage-listed chinampas remain fecund and ecologically viable even today.” And local people are working to restore and even extend the chinampas at Xochimilco.
Working with local farmers, an organization called Arca Tierra has increased the area of the chinampas by 12 acres in recent years. And Gayatri points out that this environment is home to “nearly 2 percent of the world’s biodiversity, including the critically endangered axolotl salamander.”
A major boost
Gayatri describes how the chinampas project actually got a major boost thanks to the COVID pandemic. Because of the closure of borders and restrictions on movement, food imports into Mexico’s capital had been severely curtailed.
“Mexico City’s largest open-air, wholesale market, La Central de Abasto, came to a standstill”, Gayatri wrote. This meant that the city’s residents turned to traditionally grown local foods, including the produce from the remaining chinampas.
Modern technology
Founder of Arca Tierra Lucio Usobiaga told Gayatri, “The COVID-19 pandemic demonstrated how important local farmers and community agriculture can be for creating a healthier and more reliable food system.”
And Arca Tierra helped the farmers, known as chimpaneros, to sell their produce by introducing some modern technology. It created “online portals where consumers could easily order fresh vegetables, free-range eggs, and chinampa honey”.
Chinampas are revered
Many modern Mexicans have a deep appreciation for the chinampa method: it’s recognized as an ancient system whose efficiency and sustainability make it highly relevant today. Arca Tierra agricultural team leader Sonia Tapia told Gayatri, “Chinampas are revered and venerated in our society.”
“Through chinampas”, Tiapa continued, “we not only perpetuate the knowledge and traditions of our grandparents but also preserve our relationship with nature that is several centuries old.”
Still relevant
So an agricultural system that was developed and refined by the Aztecs to meet the particular needs of their capital city, Tenochtitlan, is still relevant in our time. Much of agricultural production nowadays is highly mechanized
But the centuries-old chinampas system of exploiting natural resources in a sustainable way surely has so many ecological benefits that it can hardly be ignored. It turns out that those ancient Aztecs were really on to something when it came to agriculture!