A Mesoamerican method of agriculture, chinampa is an artificial cultivation system built in areas where water is the main natural resource present in the environment.
By Antonio Vera, Student, AG230, Sustainable Agriculture, fall 2017.
The chinampa, from Nahuatl chinampan, meaning “in the fence of reeds,” is a Mesoamerican method of agriculture and territorial expansion used by the Mexicas to expand the territory on the surface of lakes and lagoons of the Valley of Mexico. However, it is believed that it is a technique initiated in the Toltec era, although its maximum development was achieved in the sixteenth century. By 1519, this method of cultivation occupied almost all of Lake Xochimilco, and its combination with other techniques such as irrigation by canals and the construction of terraces, allowed to sustain a very dense population.
The chinampa is an artificial cultivation system that is built in areas where water is the main natural resource present in the environment, this aquifer surface is called wetland. They are built in order to grow plants, vegetables and vegetables for self consumption and local market. This farming system is placed in shallow areas of lakes, does not depend on artificial irrigation or rainwater, because its location always has irrigation.
There are two types of chinampas, the inland one, which is located on the banks and is irrigated by channels and the lagoon, which is built on water. The first step in the construction of a chinampa is to locate a shallow place on the banks of the aquifer surface, once the space is allocated it is surrounded with stakes of ahuejote, a typical tree of the wetlands, whose main characteristic is to support the excess of water. The second step is to join these stakes with reed to form a fence. Residues of aquatic plants are placed on the bottom of this to form a base that is allowed to dry approximately 15 days. Later, with a shovel with a handle long enough to reach the bottom of the lake, mud is extracted to fill the fence that forms the chinampa. It must remain fifty centimeters above the water level, again the surface is allowed to dry and it will be ready for sowing.
Dimensions of each of these gardens were 300 feet long by 30 feet wide. To make a garden, workers weaved sticks together to form a giant raft, and then they piled mud from the bottom of the lake on top of the raft to create a layer of soil three-feet thick. The rectangular gardens were “anchored” to the lake by willow trees planted at the corners. Each garden was lined on all sides by canals to allow canoes to pass with workers and materials. The chinampa were companion-planted (the planting of different crops in proximity for pest control, pollination, providing habitat for beneficial creatures, maximizing use of space, and to otherwise increase crop productivity) with corn, beans, squash, tomatoes, peppers, and flowers, and these incredible gardens yielded up to seven crops per year!
As mentioned above, the chinampa plot was constructed by staking out a rectangular enclosure, about 30 m in length and 2.5 m in width, into the marshy lakebed. The enclosure would then be fenced in by joining the stakes with wattle. After that, the fenced in area would be filled with mud and decaying vegetation. In order to prevent the roots from becoming water-logged, it was important that the fill brought the chinampa plot above the lake level. It is important to mention that the stakes used for construction, over time, become trees whose roots firmly hold the soil of the chinampa, in addition to providing shade for the vegetables. The soil extracted from the bottom of the lake is enriched with nutrients, so both elements are essential for this culture system.
Chinampas at risk
Possibly, the main attraction of the chinampas is the extraordinary fertility of the soil that, combined with the abundance of water and the labor of the farmer, became an intensive production system without equal in the world. With the urbanization of Mexico City, chinampería was lost, with the exception of Xochimilco who still practices this tradition. Among the vegetables produced under this system we can find spinach, Swiss chard, radishes, parsley, cilantro, cauliflower, celery, mint, rutabaga, chives, rosemary, lettuce and purslane, among others.
At present, in Xochimilco, the chinampas are at risk due to several factors, such as the contamination of the water, the excess of salinity in it and the loss of moisture in the soil; this is where the big problem lies for the chinampas since they depend totally on the water, which is damaged. This makes vegetables no longer fit for human consumption, since the waters have potentially toxic agents for both vegetables and soil and this makes crops more vulnerable to pests and bacteria.
Currently, according to data from the delegation, in this area there are 1800 hectares, it is known that every day the chinampera area is reduced by change to urban use, but in addition to the still productive surface only in 47.7 percent the system is applied chinampero, while greenhouses have been installed in 12.5 percent, 9.4 percent are flooded, 16 percent have grasslands and 14.4 percent produce corn. The change in the use of land is largely due to the fact that it is no longer a business for chinamperos.
Neither the development of urbanization in the Federal District nor the economic structure of the country favor the permanence of agricultural activities in Xochimilco. Farmers’ families have simply had to dedicate themselves to something else, either because agriculture does not leave a sufficient margin of profit or because it does not have enough support. It is extremely interesting that while in Xochimilco the Chinese tradition is lost, in other parts of the country that have an abundance in water, such as the marshes and floodprone areas of Veracruz and Tabasco, it is intended to introduce this farming system, an old way of producing. Nowadays it is of vital importance since it produces a large quantity of vegetables to cover the food needs of Mexicans.
This article was originally published in the CAFNRM/Agriculture Club Newsletter, Nov-Dec 2017 Issue 1.