Companion Planting 2.0 – Part 1

Background and the Three Sisters Guild

Companion planting uses both science and art to unite plants in beneficial combinations.  It is a technique based on a long history of observations of the interaction between plants in the garden.  Certain combinations of plants can add to, or detract from the abundance and health of edibles in your garden by:

1. Altering the soil,
2. Attracting or repelling insects, or
3. Creating a helpful microclimate.

Companion planting has been used for centuries.  Some plant relationships have been scientifically proven, others developed by trial and error over hundreds of years. 

I am of the opinion that this technique is a huge benefit in the vegetable garden.  Although we have a few raised beds and built planter boxes, all of our main gardening is now done as container growing using the RGGS (Rain Gutter Grow System) and the KPGS (Kiddie Pool Grow System.) This gave me a bit of a conundrum when we first began, because I had to rethink how to do the companion planting of which I had grown so fond. 

 For the purposes of this article and the videos, the focus will be primarily on “Companion Planting” in container gardening. I am developing a five part series on this topic with accompanying videos on our Youtube channel.  This part 1 will focus on the Three Sisters Guild. Part 2 will cover which vegetables are friends or foes with each other.  Part 3 will focus on herbs, while Part 4 will cover flowers.  The finale will be Part 5 where I will show you the layout of our four garden beds, what companion plants are with each of the vegetables, how they are situated in terms of spacing and placement, and the why’s of it all.

So, here we begin… Perhaps, the most well-known companions are the Three Sisters Guild (corn, beans, and squash) used by the Native Americans.  In this triad, each of the plants supports and benefits the other.

The Bean – draws nitrogen from the air and, via symbiotic bacteria, converts the nitrogen to plant-available form, supposedly boosting the growth of all three vegetables.

The Cornstalks – form a trellis for the bean vines to climb.

The Rambling Squash – with its broad leaves forms a living parasol that densely covers the ground, inhibiting the weeds and keeping the soil cool and moist.

In the Southwest, there is even a 4^th “sister” found in the guild: the Rocky Mountain Bee Plant.  This two to five foot tall, pink-flowered plant is a powerful attractant for beneficial insects that pollinate the beans and squash.  Additionally, the young leaves, flowers, and seed pods of the bee plant are edible. 

An interesting side note:  The bee plant also accumulates iron and is the source of a deep-hued paint used to create the characteristic black designs on Anasazi pottery.

Having said that… let’s talk about WHY this specific companion planting guild does NOT work well in container planting.

First, the corn…in the Three Sisters Guild, the corn is supposed to serve as a trellis for the beans.  The Native Americans developed shorter, multi-stalked cultivars specifically for this guild, such as Black Aztec, Hopi White, or Tarahumara sweet corn.  Therefore,

1.  If you are not planting one of these short multi-stalked varieties, the pole beans will likely pull over the corn.  Additionally, these varieties may or may not do well in your growing zone.
2. Proper planting of corn in the KPGS is five seven gallon bags placed in a 4’ pool, four corn per bag, or 20 cornstalks per pool.  Corn, even with adding the suggested ring of fertilizer, requires the full nutrients in the grow bag or Walmart bag…there just aren’t any nutrients to spare.  Not to mention that the corn roots are so plentiful that it requires a shovel or some other means to break and release any potting mix from them at the end of the season.

Second, the beans…

1. The common pole bean varieties such as Blue Lake may work well enough trellising up a cornstalk, but very vigorous hybrid pole beans clambering up skinny hybrid cornstalks can pull the spindly corn down.  The less vigorous climbers work the best.  Old style varieties such as Four Corners Gold and Hopi Light Yellow are traditionally used.  These legumes are not string green beans.  They are beans harvested for just the bean and not the entire pod.  The Hopi Light Yellows are actually a lima bean.
2. The nitrogen-fixing from the beans that is supposed to aid the growth of corn (a heavy nitrogen consumer,) occurs AFTER the plant has matured, produced, died, and left in the soil to decompose.  That nitrogen in only available in the potting mix the following year.

Third, the squash…

1.  The purpose of the squash in the guild is to suppress weeds and keep the soil moist.  In container growing, specifically using the RGGS and KPGS, there is no weeding and there is no watering assuming you are using the float valve as the self-watering feature of these grow systems.
2. Squash in containers gets HUGE. Take a look at the pictures below of our summer squash that is just a month planted.

In summary, if you are doing corn in a four foot kiddie pool the proper way, there just isn’t any room for other bags of vegetables.  The corn gets very dense and 8’ or more tall.  It needs the spacing and the air circulation to be healthy and produce.  The final point… there is not a symbiotic relationship to these three vegetables being “above ground” neighbors in container gardening.