The Three Sisters is a traditional companion planting method used by Indigenous peoples of America, where corn, beans, and squash are grown together. Each plant plays a role in supporting the others—corn provides a natural trellis for the beans, beans fix nitrogen in the soil, and squash acts as a living mulch, shading the ground to retain moisture and suppress weeds.
This method has been practiced for centuries, not only for its efficiency but also because it promotes soil health and biodiversity. For more details, check out this article from Native Seeds.
Planting the Three Sisters
When planting the Three Sisters, it is best to start with the corn. Once the corn plants have emerged and are about 5-10 cm tall, the pole beans can be planted. Be sure to choose a climbing variety rather than a bush bean, as the latter won’t use the corn stalks for support. This timing ensures that the beans do not overtake the corn.
If you are direct sowing the corn, this is the ideal sequence. However, transplanting corn seedlings is also an option. After the corn and beans are established, squash can be planted between them as ground cover. This could be pumpkin, butternut, or any other squash variety with similar sprawling growth.
Spacing and Pollination
I planted my Three Sisters in three rows, with about 30 cm between each plant. A larger patch can improve pollination, but if you’re working with a small space, a daily tap on the corn tassels will help release pollen onto the silks. Since each silk corresponds to a single kernel, proper pollination is key to full cobs. However, some uneven pollination isn’t a big issue.
For best results, corn should be planted in a square or circular formation rather than a single row to facilitate cross-pollination.
Soil Preparation and Timing
Corn requires warm soil, ideally around 20°C, to germinate well.
To protect seeds from birds, I found it useful to cover them with chicken wire until they sprouted.
I experimented with two rounds of corn planting:
- First planting: Early summer, as soon as temperatures started rising. My first planting was in early summer, on October 28th, with harvests from mid- to late January.
- Second planting: Midsummer (planted in the beginning of January) This batch didn’t grow as well—the plants didn’t reach the same height. The difference could be due to location, soil quality, or reduced daylight hours later in the season.
Varieties and Results
Corn: Golden Bantam, which is an heirloom Sweet corn variety. I had seeds from Livingseeds and Kirchhoff’s. Tastes less sweet than the hybrid versions you get in the stores. I planted two seeds together in case of germination problems and then went back to thin them out. They germinated within about 10 days
Beans: Pole Beans from Pro Specie Rara. Small harvest.
Squash: Waltman Butternut bought as seedlings from a nursery. In another patch, I planted watermelon seedlings. The conditions were not ideal in either case. It could be that the corn shaded out them too much. In addition, they were affected by powdery mildew.
Thoughts on My Three Sisters Experiment
Growing the Three Sisters was a rewarding experiment, even though not everything went as planned. The corn grew well in the first round, but the second planting didn’t reach the same height, possibly due to timing or location. The beans produced a small harvest, and the squash struggled—likely because it was shaded out and affected by powdery mildew. Despite these challenges, I enjoyed seeing how these plants interact and support each other. Next time, I might adjust the placing of the squash or choose different squash varieties to improve the results. Even with a few setbacks, it was a fun and interesting way to grow food, and I’d love to refine the method in future seasons. Luckily, I was able to save some seeds for next year.
Key Takeaways
- Timing matters – My first round of planting (late October) performed much better than the second (January), possibly due to better soil conditions, daylight hours, or overall plant development.
- Spacing and pollination are key – Planting in a square or block formation helps with pollination. Hand-pollinating can improve results, but some uneven pollination is not a major issue.
- Companion planting isn’t always perfect – While the corn and beans worked well together, the squash struggled—possibly due to excessive shade from the corn or powdery mildew.
- Experimentation is key – Every season is different. Next time, I might tweak the spacing or try a different squash variety to see if results improve