Three Sisters Garden: Companion Plants, Corn, Beans, Squash

Companion plantings seem to one of the latest rages in the gardening world right not.  There is of course very good reason for this, but it really isn't anything new.  In-fact, companion planting has been around for thousands of years.  It seems that only recently as people have tried to return to more sustainable, organic food production has the practice of companion planting been rediscovered.  Companion planting simply is growing two different plants in close association with one another in order to increase productivity.  For example, tomatoes and basil grow well together.  One of the better known companion planting is also possibly the oldest, known as the three sisters.  The three sisters are corn, beans and squash.  These three plants have been grown together for many thousands of years in North America.  Originally, the three sisters were used in present day Mexico but spread north and south throughout the Americas.  The spread and success of these associated crops is owed to there agricultural and nutritional compatibility. 

Agriculturally, corn, beans, and squash grow extremely well together.  The corn grows, providing a trellis for the beans to grow on.  The beans fertilize the soil for the corn and squash.  The squash provides ground cover, helping to cool and hold water in the soil for all of the plants.  Nutritionally they also work extremely well together.  Beans and corn individually do not provide the correct amino acids required by the body.  Together though they provide all the necessary amino acids making them a complete protein.  Squash provides essential vitamins and squash seeds provide healthy fats.  With all of these complementary agricultural and health benefits it is easy to see why the three sisters became dietary staples for Native Americans through out the Americas.

Today, the three sisters still work well together and can still be grown in the garden.  Planting these though requires a little more thought than just planting a patch of corn.  In order to get the three sisters to succeed corn must be planted first.  Then, after corn has grown to six inches tall, pole beans can be planted six to 12 inches away from the corn.  Squash, or melons, can also be planted at that time 12 inches away from the beans, but furthest away from the corn. I have found that if all the seeds are planted at once, the beans and squash can easily over-run the corn.  Once the beans are large enough the beans may need to be trained to climb up the corn stalk.  Squash vines also can be oriented to grow where you want them to.  Historically, some Native Americans grew their three sisters in patches of several corn stalks, several bean plants, and a few squash plants.  This seems to work best only when there is a lot of space available.  With the limited space in most peoples gardens, widely spaced rows seem to work well.  Widely spaced rows in the three sisters in was historically and still is today most common in central Mexico.  Farmers in central Mexico also add numerous other crops such as tomatoes, sweet potatoes, and tomatillos to the three sisters.  I have made numerous attempts at growing the three sisters with moderate success and plan to keep experimenting in the future until I can get a good working system.