Success with The Three Sisters – Companion Planting for Corn, Beans and Squash
If you want a stellar example of the First Peoples’ agricultural smarts, it’s hard to beat their companion planting of The Three Sisters: corn, beans and squash.
Corn, being tall and straight, provides support for the beans. Bean vines, being strong and wiry, build a framework around the corn that helps keep it from falling over. The big squash leaves cover the ground, conserving moisture and shading out weeds.
And just to put the fudge on the sundae, the beans, being legumes, provide extra nitrogen for the corn and squash.
Ever tried it?
If my own early experiments are any indication, there are a few pitfalls not mentioned: Rambunctious beans can smother the corn, or pull it over instead of holding it up; the corn and beans can shade the baby squash before it gets going, preventing it from getting going.
And while beans’ nitrogen fixing ability is legendary, even miraculous, it can’t support big crops of heavy-feeding corn and squash in addition to the beans themselves.
So is it all a romantic crock? No, it works fine – as long as you forget your usual spacings and plant the way the tribes in your area did.
Not surprisingly, the arrangement used by Northeasterners like the Wampanoag was quite different from the one employed by the Hidatsa in the Northern Plains, and both of them were different again from the water-conserving layout of the Zuni in the Southwest.
For how-to details and diagrams, go to the excellent National Agricultural Information Service (ATTRA) paper on companion planting and scroll to the bottom.
But before you get all excited, one important caveat: No matter where they were – or are, it’s not as though all of them have vanished – the gardeners who use these plans are planting corn and beans for drying, with winter squash or pumpkins. They are not trampling all over the squash for daily harvests of haricots verts or a dinner’s worth of sweet corn.
Doesn’t hurt to remember the part about burying the fish, either. A bit of extra fertilizer at planting time is pretty close to essential, especially if the soil is anything less than rich.
The close spacing used for modern corn leaves no room for beans, but you can plant squash around the edge as a weed barrier.
This brings us to Caveat #2: Some Three Sisters boosters say the prickly squash vines discourage raccoons, but I’ve never encountered a raccoon that wimpy. It takes more than a bit of discomfort to thwart an animal able to learn that an electric fence only hurts for a minute.