[Updated below] When I picked up a copy of Edible Estates (not a recommendation BTW) a while back, I came across the "three sisters" concept and decided to try it. We had our front lawn terraced over winter and I confidently expect never to mow it again, given its being buried under compost, cardboard and about 10 cm of wood chip mulch.
We plan to plant fruit and nut trees next winter but for now we have dropped a bunch of tyres onto it, filled them with Earl's Own Garden Mix (EOGM) and dropped in pumpkins, corn and beans.
So far its a success, they do seem to appreciate each other's company, the beans use the corn to climb on and in the process bind the corn stems together for support while the pumpkin shades the ground and suppresses weeds.
Although different stacks are behaving slightly differently, in the ones above the corn and the beans are going well and the pumpkin is lagging a bit, in this one, the one on the left is similar but in the two on the right, the pumpkins have gone nuts and the corn is struggling a bit.
The lush growing season is perfectly shown in this one.
The rhubarb on the left is always big but now its rampant, the lilies are in full flight, as are the flaxes, buried in the left is a tyre with 4 recently planted rock melons going well, the kumera in the middle is looking pretty happy (that is growing 2 year old tupu that I found left over from last year), and the Austrian Oil seed pumpkins are enormous and ripening already.
The funny looking frame is for cucumbers which are also going well. We sowed straight into EOGM at the base on Tuesday evening last week, by Thursday evening we had 4 seedlings and now all 9 are through.
When sowing into the tyres the optimum seems to be about 5/6 corn plants with 1/2 cucurbits sown on the north side of the tyre and 3/4 beans sown on the south side where the shade will keep them protected.
Looking at the production I would expect to get around 12/15 cobs per tyre, maybe 4 pumpkins and about 2 kilos of beans per plant.
Extrapolating that to a novice garden you could lay down 4 tyres in an east/west line which till take about 3 metres of space. I'd put them on the south side of the garden to maximise sun. Then add 200 litres of rich soil (50 litres or so per tyre) because the corn and pumpkins are gross feeders, water well and let them go to it.
You should expect about 50 cobs, 16 pumpkins and maybe 24 kilos of beans. Not bad. Of course you'll spend the winter renovating the soil, but what the heck.