So far you’ve seen an introduction to the self-sufficiency garden system, how it relates to a broad description of farms and gardens, and what food self-sufficiency can mean. Next up: exploring why gardens are inherently far more efficient than farms, especially the largest ones. Hang on; it’s quite a ride.
So just as both gardens and farms vary along physical and performance gradients, so do they vary along gradients of system efficiency, beginning with where they slightly overlap. The measures of efficiency we’ll look at are field-to-fork distance, harvested-to-consumed ratio, food footprint, and external costs. First for the industrial food system, then for the garden food system.
The Industrial Food System
1. Field-to-fork distance
In the U.S., the average distance between the point of harvest and where it’s consumed is well known: 1,500 miles. That’s true even for here in Iowa, with some of the best farmland in the world. Yet even some of the lowest-income countries also depend on distant countries for staples such as wheat, corn, and cooking oil. Every farm, from a local CSA to a mega-farm on the other side of the world, lies somewhere along this continuum.
2. Harvested-to-consumed ratio
Farm food production is all too commonly conflated with consumption, as if nothing is lost along the journey from field to fork. But that’s often far from the case. According to a University of Michigan study of the U.S. material food flow in1995, only about 15 percent of the two trillion pounds of harvested food made it to the consumer’s fork.(1) The other 85 percent dropped out along the way due to: exports; long-term storage; respiration, animal waste, and live animals; industrial uses; processing and water losses; retail losses; and food service and consumer losses. But that was 30 years ago. Since then, production of meat, which is one of the largest sources of food stream loss, has increased by 45 percent, and the industrial use of corn and soybeans going to biofuels has exploded, as have ultra-processed foods with their attendant losses. In addition, food waste has increased by 50% just since 1970. I estimate that today the harvested-to-consumed ratio is only about 5%, if that. It would be nice to see a team of agricultural economists update this graphic, but I doubt that anyone in modern agriculture really dares to reveal what it would look like now.
Some argue that this graphic doesn’t fully reflect the value of agricultural exports, which they portray as a big plus for the US. Yet U.S. food exports are largely offset by imports. In fact, in 2023 and 2024 imports exceeded exports by 15-20%. Granted, that’s in cash value, not material biomass as shown in the graphic. Still, we import a lot. For instance, a third of our vegetables and half of our fruits are imported. All food things considered (and there’s much more in play here than biomass or cash totals), it’s an open question as to whether our exports are a net positive.
Another argument is that all of the components that drop out can be thought of as legitimate costs of doing business. However, that’s only if you frame externalized collateral damage as legitimate, provided you can get away with it. We’ll get to negative externalities in a bit.
3. Food footprint
Also known as agricultural land per capita, this is the total amount of pasture and cropland required to feed the average person. Of course, it isn’t the same for every country or region. For the U.S. (together with Canada, shown below as Northern America), the FAO reported as recently as 2022 that it was about 3 acres. Then it decided to add in Mexico, which resulted in a combined figure for North America of 2.5 acres. For sure Mexico’s much lower footprint is what pulled it down. Why am I so sure? Well, note that various other regions of the world are also much lower, and not just because they’re developing countries. Western Europe—typically regarded as having a fully industrialized food system—requires only 20% as much land to feed a person as the U.S. Could that be due—at least in part—to the west Europeans consuming only about half as much meat per capita as Americans, and having around half of our rate of obesity? To be sure, the U.S. has shaved a good bit off its food footprint since 1961, but it still lags far behind western Europe and SE Asia.
4. External costs
Does it surprise anyone that the industrial food system covers only about a third of its “true cost” of doing business? Over decades, it has managed to foist off the remaining two-thirds onto other segments of society. In other words, it has “externalized” the great majority of its health, economic, social, and environmental costs. These very real expenses are covered not by the industrial system but by taxpayer-funded government subsidies, higher insurance and health care costs, environmental cleanup costs, other business sectors’ labor and financial costs, and so on. The result is artificially low prices at the grocery store checkout, the lowest in the world as a percentage of average income. But the cumulative real costs don’t just disappear. In fact, they annually add up to trillions of dollars for the U.S., and between $10 and $20 trillion globally, according to a raft of true cost mega-studies.
A typical example of negative externalities is the nitrate-removal facility (top left, above) in the Des Moines, Iowa Waterworks Treatment Plant. Nitrate, which is toxic, seeps from agricultural fields into the drinking water supply, from which it has to be removed. This facility that does this cost millions of dollars to build, maintain, and upgrade, all funded by taxpayers, not the farmers or anyone else along the industrial food chain. Moreover, once removed the nitrate goes right back into the Des Moines River, from where it and the rest of the polluting agricultural chemicals from the Midwest wash down to the “dead zone” at the mouth of the Mississippi near New Orleans, costing the fishing industry there further millions in losses.
Now, by way of striking contrast to the industrial food system . . .
A Self-Sufficiency Garden Food System
1. Field-to-fork distance
Most self-sufficiency household gardens will be in someone’s yard, in which case the garden-to-fork distance can be as little as 15-20 feet. However, I have driven or bicycled the 6-mile round trip to my garden in 2023 and ’24. Meanwhile, Leonid Sharashkin notes that Russian owners of dachas or other private plots drive as far as 20 km or more to tend their gardens.(2) In Germany, many people have small garden plots with little sheds next to railways. Variety happens. Still, here in the U.S., where some will circle round and around to find a parking place a little closer to the grocery store, I suspect most people will want to garden in their own yard.
But suppose someone replicates my garden. Could they really live off it for a year? I would say Yes, they could, based on:
• My 30-day experiment in a portion of my 2020 garden, followed by producing a year’s worth of meals in my 2021 garden of 35’x40’.
• A permaculture garden that produced over twice the weight of vegetables per square foot (3) as my garden did.
• A study published in the Proceedings of the National Academy of Sciences reporting that the yield of vegetables in home gardens was twice that of commercial farms.(4)
• The fact that those gardens also delivered at about twice my rate of yield.
• The performance of victory gardens. During World War II, 20 million Americans produced 40% of the nation’s vegetables—as amateurs, on short notice, with little training. As has happened in other countries when need comes to shove.
• Evidence that household plots can be massively scaled: Again, Russia’s gardeners supplying half their country’s food on just 3% of the country’s agricultural land.(2)
Then there are community gardens. They provide inspiration and wherewithal for people to grow a few veggies they otherwise couldn’t. However, they don’t provide more than a few days’ worth of self-sufficiency, if that. In most cases each person is given something like a 4’x12’ raised bed. It’s a start, and that’s important and encouraging. But ideally, if the ultimate goal is to provide an extended, continuous supply of food, each gardener would need much more space. I have not yet seen or heard of a community garden that does that, despite some of their administrators claiming that they supply food for hundreds of people in the vicinity. Maybe they do, but you can bet they provide only a small fraction of any one person’s sustenance, and usually not a balanced diet at that. So IMO the concept of community gardens needs to evolve a good bit from where it is now if it’s to supply a significant degree of self-sufficiency. Maybe in gradations from smaller to increasingly larger allotments per person . . . as they prove themselves capable of managing them . . . which would require more land devoted to community gardens . . . and a capable entity to organize them . . . and so on. But to get back to that first measure of efficiency, community garden-to-fork distance would still be orders of magnitude less than that of most farms.
2. Harvested-to-consumed ratio
I’ve found this ratio to be at least 90%, just because the journey from my garden to my plate is so much simpler, shorter, and more direct. No 1,500 miles worth of multiple changes of hands, shipping containers, factory processing, and food packaging. It eliminates industrial uses; reserve storage; exports; and no or far less per unit of harvest in animal waste, respiration, water, retail, processing, and consumer losses.
Not that this—or other points made here—by any means addresses all of the “Yes, but . . .” doubts around a self-sufficiency garden food system. Which is why I’ll return to such concerns in later posts. In the meantime, for the sake of laying out the broad view, let’s move on.
3. Food footprint
When you can feed a person for a year on a 35’x40’ self-sufficiency garden (1,400 ft2), the food footprint is 0.03 acre, which is 1 percent of the 3.0 acres required by the U.S. industrial food system. To put it another way, think about 100 such gardens spread around a town or rural region. That would add up to 100 acres, which would feed 100 people. As opposed to 3 acres of agricultural land in our industrial system, which feeds only 1. Is the potential advantage of a self-sufficiency garden food system beginning to shine through the clouds of misperceptions about farms and gardens?
4. Garden external costs
Basically, there would be virtually none. However, there could be damaging drawbacks from some aspects of home gardening, such as the tendency of some gardeners to use much greater quantities of chemical pesticides and fertilizers per unit of food produced than in conventional agriculture. That outcome could be even more worrisome when children help, just because they are more sensitive to unhealthy levels of pollution than adults. In addition, there are legitimate concerns about urban gardens near busy streets, where exhaust fumes of traffic could pollute both gardeners and produce. However, the great majority of gardeners—being attuned to values of naturalness—are more likely than not to avoid use of synthetic chemicals and sites near traffic fumes.
Chemicals or not, some people might throw out their backs or otherwise overextend themselves. That, along with pollution, could conceivably up their medical bill. Nevertheless, these kinds of costs would not be handed over to the neighbors to pay as externalities. No gardener would even think of doing that. But it happens routinely, on a colossal scale, in the industrial food system.
Other considerations
Not included in these measures of efficiency are water and energy, which are more difficult to quantify for a garden-based food system. Nevertheless, we know that industrial agriculture commands some 70 percent of our water use and 20 percent of our energy usage. Imagine how massive adoption of self-sufficiency gardens could help conserve these increasingly threatened resources, especially water in the Southwest. And consider how drastically reducing the 50% of U.S. greenhouse gas emissions produced by industrial food, farming and land use (5) could help mitigate global warming.
So in the big picture the real economy of scale, with greater efficiency by orders of magnitude, would accrue not to the vaunted industrial food system, but to self-sufficiency gardens adopted nationwide. I have shopped this presentation around, and researched conventional food and garden food systems at some depth, and have diligently searched for—but not yet found—a way to avoid this conclusion. I’d love to have some expert agricultural economists see if they can find some fatal flaw in my data, conceptual framework, or reasoning, but so far that hasn’t happened.
Of course, we don’t yet have such a system, but we do have the beginnings of one: 41% of American households have a home food garden of some kind, so the basic infrastructure is already in place. Given the industrial system’s enormous inefficiency, its shaky response to the Covid upheaval, and the greatly increased climate change threats to food production, the need to have a robust and resilient alternative is urgent. More on that later.
And now for closing point no. 1: I do not propose completely replacing the industrial system with gardens; that would not be feasible. However, a ratio of 50% gardens to 25% community food streams and 25% distant food sources would be a goal worth pursuing, and feasible. If Russia can produce 50% of its food by gardens in a forbiddingly northern climate, there’s no reason why we, with a much friendlier latitude and many other advantages, couldn’t do it. Note also point no. 2: Russia’s ability to do it on just 3% of its agricultural land closely approaches the self-sufficiency garden food footprint, which is just of 1% that of the U.S. industrial system. And finally, point no. 3: the proposed effort to massively scale self-sufficiency gardens would not involve trying to change the industrial system; it will do that itself, at its own pace and in its own way. That is, as best it can; more also on that later. Lots of reason here to be optimistic about what can be accomplished by amping up gardens. Stay tuned.
(1) Center for Sustainable Systems, University of Michigan. 2024. "U.S. Food System Factsheet." Pub. No. CSS01-06. https://css.umich.edu/publications/factsheets/food/us-food-system-factsheet
(2) Sharashkin, L. 2008. The socioeconomic and cultural significance of food gardening in the Vladimir region of Russia. PhD dissertation, University of Missouri.
(3) Graven, A. 2022. 7,000 Pounds of Produce on 1/10th of an Acre. Ambrook. https://ambrook.com/blog/a-visit-to-the-farm/how-the-urban-homestead-feeds-its-community-with-help-from-ambrook
(4) McDougall, R. et al. 2018. Small-scale urban agriculture results in high yields but requires judicious management of inputs to achieve sustainability. Proceedings of the National Academy of Sciences. 116 (1) 129-134.
(5) Cummins, R. 2019. The 9-Percent Lie: Why are the USDA and EPA hiding the fact that half of all US greenhouse gas emissions come from industrial food, farming and land use? https://organicconsumers.org/nine-percent-lie/?utm_medium=email&utm_source=engagingnetworks&utm_campaign=OB+717+Saturday&utm_content=OB+717+Saturday