The Legend of the Three Sisters
The term Three Sisters emerged from the Iroquois creation myth. It was said that the Earth began when Sky Woman who lived in the upper world peered through a hole in the sky and fell through to an endless sea. The animals saw her coming, so they took the soil from the bottom of the sea and spread it onto the back of a giant turtle to provide a safe place for her to land. This Turtle Island is now
what we call North America.
Sky woman had become pregnant before she fell. When she landed, she gave birth to a daughter. When the daughter grew into a young woman, she also became pregnant (by the West wind). She died while giving birth to twin boys. Sky Woman buried her daughter in the new earth. From her grave grew three sacred plantscorn, beans, and squash. These
plants provided food for her sons, and later, for all of humanity. These special gifts ensured the survival of the Iroquois people.
Companion planting can be described as the establishment of two or more plant species in close proximity so that some cultural benefit (pest control, higher yield, etc.) is derived. The concept embraces a number of strategies that increase the biodiversity of agroecosystems. Generally, companion planting is thought of as a small-scale gardening practice.
Companion planting in gardening and agriculture is the planting of different crops in proximity for any of a number of different reasons, including pest control, pollination, providing habitat for beneficial insects, maximizing the use of space, and otherwise increasing crop productivity. Companion planting is a form of polyculture.
Companion planting is used by farmers and gardeners in both industrialized and developing countries for many reasons. Many of the modern principles of companion planting were present many centuries ago in forest gardens in Asia, and thousands of years ago in Mesoamerica.
The Scientific Foundations for
While conventional agriculturalists and BD
practitioners may disagree over the validity of
sensitive crystallization research, there is
general agreement today on the validity of
several mechanisms that create beneficial plant
√ Trap cropping. Sometimes, a neighboring
crop may be selected because it is more
attractive to pests and serves to distract them
from the main crop. An excellent example of
this is the use of collards to draw the diamondback moth
away from the cabbage.
√ Symbiotic nitrogen fixation. Legumes.
such as peas, beans, and clover. have the
ability to fix atmospheric nitrogen for their
own use and for the benefit of neighboring
plants via a symbiotic relationship with Rhizo-
bium bacteria. Forage legumes, for example,
are commonly seeded with grasses to reduce
the need for nitrogen fertilizer. Likewise,
beans are sometimes interplanted with corn.
√ Biochemical pest suppression. Some
plants exude chemicals from roots or aerial
parts that suppress or repel pests and protect
neighboring plants. The African marigold, for
example, releases thiophene, a nematode
repellent, making it a good companion for a
number of garden crops. The manufacture and
release of certain biochemicals is also a factor
in plant antagonism. Allelochemicals such as
juglone. found in black walnut. suppress the
growth of a wide range of other plants, which
often creates a problem in home horticulture.
A positive use of plant allelopathy is the use of
mow-killed grain rye as a mulch. The
allelochemicals that leach from rye residue
prevent weed germination but do not harm
transplanted tomatoes, broccoli, or many other
√ Physical spatial interactions. For example, tall-growing,
sun-loving plants may share space with lower-growing,
shade tolerant species, resulting in higher total yields
from the land.
Spatial interaction can also
yield pest control benefits. The diverse canopy
resulting when corn is companion-planted
with squash or pumpkins is believed to
disorient the adult squash vine borer and
protect the vining crop from this damaging
pest. In turn, the presence of the prickly vines
is said to discourage raccoons from ravaging
the sweet corn.
√ Nurse cropping. Tall or dense-canopied
plants may protect more vulnerable species
through shading or by providing a windbreak.
Nurse crops such as oats have long been used
to help establish alfalfa and other forages by
supplanting the more competitive weeds that
would otherwise grow in their place. In many
instances, nurse cropping is simply another
form of physical-spatial interaction.
√ Beneficial habitats. Beneficial habitats.
sometimes called refugia.are another type of
companion plant interaction that has drawn
considerable attention in recent years. The
benefit is derived when companion plants
provide a desirable environment for beneficial
insects and other arthropods. especially those
predatory and parasitic species which help to
keep pest populations in check. Predators
include ladybird beetles, lacewings, hoverflies,
mantids, robber flies, and non-insects such as
spiders and predatory mites. Parasites include
a wide range of fly and wasp species including
tachinid flies, Trichogramma, and
ichneumonid wasps. Agroecologists believe
that by developing systems to include habitats
that draw and sustain beneficial insects, the
twin objectives of reducing both pest damage
and pesticide use can be
√ Security through diversity. A more
general mixing of various crops and varieties
provides a degree of security to the grower. If
pests or adverse conditions reduce or destroy a
single crop or cultivar, others remain to produce
some level of yield. Furthermore, the
simple mixing of cultivars, as demonstrated
with broccoli in University of California research,
can reduce aphid infestation in a crop. (ATTRA, 2007)
It doesn’t just matter what plants you grow, it also matters where you plant them. As author Jessica Walliser explains in her book, Plant Partners, gardens are “an ecosystem rather than a contrived environment,” and choosing to grow certain plants together can be the secret to gardening success. Companion planting works by pairing the right plants in garden beds to enhance the growth of one or both plants. But what are companion plants exactly?
Companion plants are plants that benefit each other in at least one way. Those benefits can include natural pest control, increased pollinator activity, improved plant and soil health, added shade and support, weed suppression, and better disease resistance.
One of the most classic examples of companion planting is the Three Sisters, which was developed by Native American cultures centuries ago. In this companion plant pairing, corn, squash, and climbing beans are interplanted together to enhance the growth of each other. The corn provides support to the beans, the beans boost soil nutrients due to their nitrogen-fixing abilities, and the squash’s large leaves shade the soil to conserve moisture and block weeds.
The Three Sisters is just one example of companion planting, although there are many more.