*Lakota greeting*

Hello, my name is Tada Vargas and I'm  an intern with the National Laboratory  

for Genetic Resources Preservation. NLGRP is  located here in Fort Collins, Colorado--ancestral  

homelands to the Arapaho, Cheyenne, Ute, and  Oceti Sakowin. Today we will be discussing  

three sisters agriculture which involves corn,  beans, and squash. Three sisters agriculture  

is an Indigenous historical practice and  a great example of companion planting.

Have you ever heard of three sisters gardening?  This practice is a historic gardening or  

agricultural planting scheme in which certain  crops are planted in close proximity to one  

another. By planting in this way, the different  crops not only improve their own health and yield  

but also that of their companions  or sisters. These benefits are not  

only expressed in the current growing  season, but in the next season as well.

Where did three sisters planting originate? 

Three sisters gardening is a historic  and traditional Indigenous agricultural  

practice that originated in Central Mexico  and spread throughout the Americas by 1000 CE.  

Although this unique gardening practice is  typically synonymous with the Northeastern tribes,  

many indigenous groups across North America  have utilized some version of this type of  

companion agriculture. This map shows some of the  regions where three sisters were planted together.  

The dark blue region is the  Haudenosaunee or Iroquois people;  

the light blue are the Anishinaabe or Chippewa  and Ojibwe tribes; the small pink is the Mandan;  

the brown is the Ho Chunk  tribe; the yellow is the Pawnee;  

the orange are the Hopi and Dine or Navajo people;  the purple is the Tarahumara people; and the green  

are the Cherokee, Chickasaw,  Choctaw, Creek, and Seminole tribes.

Who are the three sisters? The short answer is corn, beans,  

and winter squash or pumpkin; however, particular  varieties of each sister have been shown to relate  

best with one another in a symbiotic  relationship. Different tribes have their  

own specific planting methods as well as unique  varieties that worked best in their conditions.  

Corn, also known as maize, is always planted  first. As the eldest sister corn stalks provide a  

strong, tall foundation for her other two sisters.  Her stocks help reduce competition for sunlight  

by creating a supportive vertical space for beans  to grow upward, thus freeing the ground level for  

squash to thrive horizontally. Corn's support  extends below the surface as well. Her thick and  

fibrous root system provides a dense foundation,  giving the other sisters stability. Corn roots  

utilize nutrients in more shallow levels of  the soil profile compared to her sisters.

About two weeks after the corn has been planted  or when she has emerged 4-6 inches above the soil  

surface, the beans are planted. The bean  variety needs to be a vining or pole bean  

rather than a low growing bush bean. As the  bean plant grows, she will wind her vines up  

her elder sister's stalks. This symbiotic  relationship provides a safe space for the  

beans to climb and the intertwining bean vines  stabilize and support corn's stalks. Beans also  

assist both the corn and squash through their  taproot system. The root system of the bean not  

only grows in a downward direction so as to not  take surface water away from the other sisters,  

but it also has a unique capability to capture  the essential nutrient nitrogen from the air.  

Rod-shaped bacteria called rhizobia establish  their symbiotic association with the beans by  

forming root nodules--small growths in which the  bacteria reside. Rhizobia are able to convert  

nitrogen gas into ammonia, a form that can be  used by plants to make amino acids, proteins,  

DNA, and other essential compounds. In return  the legume provides carbohydrates to the bacteria  

as an energy source. Though the nitrogen obtained  in this way is readily available to the beans,  

a majority of the converted nitrogen will not be  available to the maize and squash until the next  

growing season. The legume root system will need  to break down in order to release the nitrogen.

Last but not least, the squash is planted. The  seed of the younger sister is sown at least one  

week after the beans have been planted or after  they have begun to emerge through the soil. Squash  

grows in a sprawling manner, therefore her prickly  vines and large, prickly leaves naturally protects  

her sisters by inhibiting pests from coming near  them. Also, her large leaf size helps suppress  

weeds and retain moisture by shading the soil.  As the squash vines sprawl in all directions they  

sprout roots at points far away from the other  sisters, thus reducing competition with them.

When do we begin planting and where? 

Since the three sisters do not tolerate frost  well, they are known as warm season crops.  

Maize is typically planted in mid to late May  in the Northeast when the ground is no longer  

cold and wet. Traditionally the Haudenosaunee  begin planting when the dogwood leaves are the  

size of a squirrel's ear. The three general  planting techniques are the mounding method,  

the field method, and the  landscape or rotational method.

The mounding method is typically used in  regions where rainfall is abundant. In this  

technique the three sisters are all grown in  the same mound, generally with three or four  

seeds each of corn and beans, and two seeds  of squash. If multiple mounds are planted,  

they should be spaced about  three to four feet apart.

In the field method the sisters are grown  in a square plot. The corn is planted in  

the center in rows, and then the beans  surround the corn in an outer square.  

The squash is planted along one  or two sides of the square plot.

The landscape or rotational method is typically  used where precipitation is least abundant.  

These sisters are planted in their  own plots adjacent to each other.  

After each season the crops  are rotated to the right.  

Since corn requires a high level of soil  nitrogen, it is important that corn follows beans.

Why are these three crops significant? The three sisters complement each other  

in their own special ways: corn creates a  vertical growing space and structural support,  

beans replenish the soil with essential nutrients,  and squash wards off pest and helps retain water.  

Research has shown that planting  the sisters together results in  

a yield increase of up to 30 percent  compared to planting them separately.

Three sisters gardening also preserves traditional  agricultural knowledge, reduces the dependence on  

pesticides and synthetic fertilizers, and  provides a hands-on relationship with food.

The three sisters were essential for the survival  of Indigenous peoples and early European settlers.  

Together they provide essential nutrients  for meals to last through long, harsh winter  

months. Maize is not only a carbohydrate source,  but its high fiber content aids in digestion.  

Also, it provides a source of B vitamins and  minerals like zinc, copper, and manganese.  

Beans are high in amino acids, which  are the building blocks of proteins.  

They are high in soluble fiber and provide other  important vitamins and minerals like folate,  

iron, potassium, and magnesium. Squash and  pumpkin provide an abundance of antioxidants.  

One serving of butternut squash provides  more than 100 percent of the daily vitamin A

requirement and nearly 40 percent  of the daily vitamin C requirement.

Historically, the three sisters were most likely  dried for food storage and later prepared in  

a soup. Society has become more creative in  their three sisters dishes including burritos,  

casseroles, stews, and stir fries. There are  many communities which do not have easy access to  

healthy foods, therefore three sisters gardening  is returning as a heavily relied on practice  

which can improve community nutritional status  and aid in communal food sovereignty efforts.