I've read about this for some time, but this year I've got myself a packet of these seeds and this weekend I'm going to plant my own Three Sisters Garden. From the seed pack,
According to Iroquois legend, corn, beans and squash/pumpkins are inseparable sisters, precious gifts from the Great Spirit. The tradition of interplanting them in the same mounds is actually a sophisticated, sustainable system providing long-term soil fertility and healthy harvests.All three of these seeds can be planted now. Renee's Garden has put together the seeds in a special pack, but you don't have to use her seeds. You will want to take advantage of the detailed instructions on her website, however, and browse around a bit ... there are some great annual seeds that will also grow if planted now ... just sayin...
Earth-Tones Indian Dent Corn provides natural poles for bean vines to climb and the beautiful dried ears make tasty cornmeal and/or decorations.
Rattlesnake Bean Vines support the corn stalks and fix nitrogen on their roots to improve soil fertility. Blossoms attract pollinators and high-protein dried beans are great for chili.
Shallow-rooted Sugar Pie Pumpkin Vines make a living mulch, shading out weeds and preventing moisture loss. Use Sugar Pie Pumpkins for tasty pies and holiday celebrations.