I have three “Tree Sisters” patches, with 10, 15, and 25 squares. In all the patches, I planted or I am planning to plant 2 beans in each corner, then either 2 corn in each square or 4 corn in every even square, and either 1 pumpkin in each square or 1 in every odd square.
So I crunched some numbers to see how much of the full capacity of these areas I am using concerning each plant:
~80% for the beans
~90% for pumpkins
~30% for corn
So overall, I am using only half the area that I would need if I were growing each of the crops separately at optimal spacing. Which is one of the points of using the companion-plant system.
I do not know whether this ratio is good, bad, or ugly. To be completely honest, I did not look it up, and I am playing it by the ear. I planted the beans as a main crop because I have marginal soil, and I know beans thrive on it and will improve it. Then I planted only as much corn as I had receptacles for. And I might plant even more pumpkins than I initially planned because one of the seed suppliers had almost a miraculous germination rate and I loath to toss a viable plant.
That last point is still not entirely decided. I already planted 10 marrow squashes, and so far they have survived and started to grow. Today I also planted the first 3 Hokkaido because they had three true leaves and thus should, hopefully, be sturdy enough to survive slugs (I will add slug pellets around them anyway). The butternut squashes still have a huge question mark over them, but if they survive, I might have to establish a solitary patch for some of them. I do have the place, although I do not know if I will have the strength.
I will probably have to add some liquid fertilizer to the irrigation water due to the marginal nature of my soil. The improving effect of beans will only show up in the subsequent years. I do not know if the plants will grow to their full capacity or if the capacity of each species is going to be diminished. Unless it is reduced by more than half, the patches should produce more than separated ones would.
Based on past experience, if grown separately, I should get around 70g of beans, 50 g of corn, and 5000 g of pumpkin on average from one plant. So if all plants grow well, I might be looking at about 30 kg of beans, 5 kg of sweet corn, and 150 kg of pumpkins. I will only believe those numbers when I see them, and out of all of these, I am most inclined to believe the first and the last one. Of all these, it is usually the corn that performs the poorest.
I did try corn as a companion plant to potatoes about five years ago. I did not write about it, but it was a success – the potatoes grew at 100% capacity, and thus all the corn was extra, albeit a small amount. Shame that it is so much more work to grow everything here. I could get a lot more use out of my garden if I could just toss seeds in the ground and let them grow. It is one of many downsides of living in a semi-mountainous area. Sigh.
Now I’m going outside again.