I absolutely did Not know this - but I do now. I have often heard of The Three Sisters, without full recognition of the relationship. I will be planting my corn, beans and squash in a quite different pattern this year. In fact, I think I will plant it in that sunny space behind the house and actually name it My Three Sisters Garden. I came across this in my morning reads - attributed to a post at one of my listserv groups by Sweet Spring Farm.
*The Three Sisters*
The "three sisters" of New Mexican agriculture, corn, beans, and squash,
were hundreds of years ahead of their time. This system serves as the basis
for inter-cropping systems currently being used around the world as tools to
increase agricultural productivity in areas facing food shortages. Why is
this such a successful system?
Simply stated, each of the three sisters serves an important role. To
understand the system, one should first consider the three plants
seperately. Growing corn in rows is a good idea but wastes valuable planting
space. Beans require some sort of support system and must be staked up to
grow. Finally, both squash and corn require additional nitrogen in the soil
to produce adequately in New Mexico's typically sandy soils, which are also
prone to losing valuable moisture due to evaporation.
As corn reaches for the sun, beans may grow up the strong stalks and the
necessity of building a support system or frame is reduced. One must plant
corn some distance apart, leaving the ground bare; however, planting squash
between the rows of corn reduces soil moisture loss as the squash foliage
acts as a natural mulch, reducing soil temperatures and helping to "hold"
moisture in the soil where it may be used by the plants and not lost to the
atmosphere. Finally, beans have the unique capability of being able to "fix"
atmospheric nitrogen, pulling it from the air and improving soil nitrogen
status; essentially, "fertilizing" the other two sisters.
Contributed by Dr. Dann Brown, Professor of Botany, Eastern New Mexico