He wouldn't grow anything. However, the seeds he scattered would collectively decide which ones would get what space and they would soon take over the garden, the house, and begin encroaching on the neighbors.
He would still have to choose what to grow. You (in your idealistic view) could say that he isn't choosing, but given that he has a small-scale backyard to work with, how many different plant species do you think would be utilized? Do you see my point?
I suppose if the place started out as a tangle of poison ivy, even he, with his let-nature-decide attitude would choose to replace that species with other, more useful ones. But there are so few truly nasty weeds that have to be eradicated and so many choices of useful plants that the combinations and the possibilities are endless.
My own experience planting the side of my back deck has led me to see the benefits of the let-nature-decide attitude. First I tried squash. That was OK, but it wasn't a perennial and it had blackberries growing into it. Next I tried scarlet runner beans. Must not have been enough sun or something, because only a couple got big enough to flower. And they had trouble competing with the blackberries. Then I did the Fukuoka thing of "if blackberries want to grow, encourage the blackberries". This is turning out much better.
I'm still trying to come to a happy medium between let-nature-decide and my own visions of what the garden should look like.
Craig Holman wrote:He would still have to choose what to grow. You (in your idealistic view) could say that he isn't choosing, but given that he has a small-scale backyard to work with, how many different plant species do you think would be utilized? Do you see my point?
i believe he would try anything he could get for cheap/free, without excessive preference, as long as it seems like it had a fairly good shot at growing in the climate.
i also think he would grow many common things, and not undervalue them, because these are found more easily.
as opposed to trying to get fancy unusual named special cultivars and such, especially those that arent totally edible...like all that interesting stuff that isnt commonly known about thats technically edible, but not considered desirable edibles. but then again i think if he obtained a jar of seeds of something like this i can see him throwing that out to with the rest and letting whatever take root grow.
This isn't really a hypothetical question because Fukuoka had a backyard garden. At least that's what I've heard. By 'backyard garden' you mean a garden primarily for kitchen food, right? He probably grew things for the kitchen in a natural polyculture seeded with seedballs - just a guess.
From what I know, he had a rice field, an orchard, and a kitchen garden.
A good research query for someone who has the more practical fukuoka book or knows Larry Korn.
here is a quote from Larry Korn about Fukuoka's zone one garden....
"I mentioned that Fukuoka's farm is a fine model of permaculture design. In Zone 1, nearest his family home in the village, he and his family maintain a vegetable garden in the traditional Japanese style. Kitchen scraps are dug into the rows, are crops rotated and chickens run freely. This garden is really an extension of the home living area."
Wouldn't substituting blackberry with thornless blackberry work? You could either go napalm and switch or gradually introduce the target species.
I think people can get hung up on the 'do-nothing' and the 'let nature decide' ideas. In my plot, if nature was deciding it would grow a field of grass and goldenrod > toward black locust > toward oak, chestnut, hazelnut. I keep goldenrod and grass, but they get seriously limited in their ability to express themselves. Technically, I'm part of the nature there, and I'm deciding to have things I want without creating a huge disturbance. I have zero cognitive dissonance about this.
Anyway, finding natural equivalents is useful. Goldenrod grows, and so that means sunchokes will also grow well, which they do. Most weeds have their cultivated counterparts which are good choices for substitution.
The other is finding where nature is heading and push it in that direction. That is 'doing nothing against nature' which is the original meaning of 'do nothing'.
In an urban backyard there is so much that is a result of human interaction that finding out what nature would do is more difficult and might change from one meter to another, as conditions can be vastly different. You're working within a situation in which nature is guided substantially by the human element which can be for the better or the worse, depending on the human. I recently let a shady urban garden go, mint and cinquefoil took over. It really depends on your own needs and what the site has to offer and your range of possibilities for substitution.