When you think of farming you typically think of one crop in the field. That was how I was taught to grow vegetables, and I would say every farmer grows the same way; but things are changing. In my humble opinion, if a farmer is any good, she is always observing. Over the years, I have seen people plant many different species of crop in the cover crop fields. As an example you wouldn’t just grow vetch to increase nitrogen in the soil for your next crop, you would include a wide variety. Many of us observed the benefits of a community of plants in the field, simply put increased yields, better results. The cover crop we have this year has 8 different plants, and it is absolutely thriving!
I came across some research by farmers in ND where cover crops were planted individually and the last planting was all 10 varieties planted together. The total seed of the last row was the same as the individual row, so no extra seed was planted. It was a dry year. Most of the single seeded rows did not survive, but the multi-seeded row grew extremely well. This showed us that there is much more going on than simply sowing seeds for the crop to survive.
Over the last couple of years, we have planted a multitude of vegetables in the same bed, for example lettuce, fennel, kale. Although I don’t have the time to measure, my observation has been they all thrive. For the coming fall all of our cabbages will be mixed. That is 12 different varieties of cabbage planted in the same bed. Community is something that helps us all thrive, and apparently it is the same for plants!