How To Grow Sweetcorn, Beans and Squashes Using The Three Sisters Method

The tradition of growing sweetcorn, beans and squashes together is laid down in the stories of the Iroquois people (Native North Americans) who believed that corn, beans and squash were three inseparable sisters and would only grow and thrive together. Bringing things right up to date, it is easy to see that the tradition describes a sustainable growing method providing long-term soil fertility and maximising growing space.

The sweetcorn provides a natural support for the beans whilst the beans help to stabilise the corn plants, making them less vulnerable to blowing over in the wind. The shallow-rooted squash plants become a living mulch, smothering emerging weeds and cutting down on water evaporation from the soil, thus improving the crops' overall chances of survival in dry years. The beans fix nitrogen on their roots, improving the fertility of the soil for the following year. Couple that with the huge amount of vegetation produced by the combination that can be dug in or composted and the sustainability of the method soon proves itself.

Success in growing using the Three Sisters system does need some careful attention to timing and seed spacing; if you simply plant all three in the same hole at the same time you will end up with a tangle of beans and squashes fighting for supremacy, overwhelming the sweetcorn completely! You may use any of our varieties of Sweetcorn and either Climbing French Beans, Runner Beans or Borlotto Beans. All our Squash and Pumpkin varieties are suitable for this planting scheme, though those with a trailing habit (Winter Squashes and Pumpkins) will obviously cover a greater area.

Planting Out

Ideally, you need an area a minimum of 10 x 10 feet (3 x 3 metres). Should you wish to scale up that is fine; if you scale down for smaller areas you may find that your sweetcorn may not pollinate properly and you will not get full cobs.

• With string lines mark off three 10 feet (3 metres) rows, 5 feet (1.5 metres) apart.
• In each row draw up the soil in five mounds approximately 18" (45 cm) in diameter and 2½ feet (75 cm) from the centre of one to the next.
• Starting with one of the outer rows, put 4 sweetcorn plants in the second and fourth mounds. Set the plants out 6" (15 cm) apart in a square pattern.
• In the middle row, put 4 sweetcorn plants in each of the first, third and fifth mounds. Set the plants out 6" (15 cm) apart in a square pattern.
• In the other outer row, put 4 sweetcorn plants in each of the second and fourth mounds. Set the plants out 6" (15 cm) apart in a square pattern.
• When the sweetcorn has grown to around 12" (30 cm) tall you can plant out your squash plants and sow your bean seeds. First, weed off the entire patch before sowing 4 bean seeds in each sweetcorn mound. Sow the seeds equally spaced 3" (7.5 cm) away from the sweetcorn plants.
• Now plant two squash plants in each of the vacant mounds (1, 3 & 5 in row one; 2 & 4 in row two; 1, 3 & 5 in row three).

With your planting now completed all you need do is weed until the squashes have covered the ground, and water as required, harvesting the crops as they are ready.