35
$\begingroup$

One person lives alone with access to a small patch of useful land. They have to grow all their own food and survive indefinitely.

  • This small patch of fertile soil is the only useful land. No grazing, everything around them is basically rocks.
  • They have averagely rich and deep topsoil, access to water, and a temperate climate (e.g. England, Germany, Oregon).
  • Soil erosion will be negligible.
  • They have access to simple hand tools, but not chemicals, motors, or electricity.
  • They have seeds for any plants you could name, and a minimal stash of food to survive until crops come in.
  • They have materials such as wood and plastic.
  • No fertilizer, but they can recycle their waste.
  • Assume no complete disasters, predators, etc, but there will be loss to pests, rot, and poor weather.
  • They have cool, dark, almost-airtight places to store food, but no salt, vinegar, or other preservatives unless they make them from scratch.
  • This person is physically active, so needs 2,000-3,000 kcal/day.
  • The goal is to survive indefinitely with good health. Decades at least.

How small could this patch of land be?

To what extent could they make this a closed loop? Will the soil eventually become unusable even if they compost their food scraps, faeces, and urine?

What strategies would be effective at this small scale? Does it make sense to plant homogeneous crops or strive for diversity? Does it make sense to have crop rotation? Does it make sense to divide the soil and e.g. alter the pH of different sections? Does it make sense to cultivate things which will not produce for years?

$\endgroup$
12
  • 2
    $\begingroup$ Just for food one acre should be enough. If they also need fibers for ropes and textiles (e.g., hemp, flax) then two acres or 1 ha. If they also want some sheep for meat and wool then four acres or 2 ha. If they also need some wood for fuel or construction then this is extra. Of course they need to alternate crops, manage the soild carefully etc. But soil depletion is not really a problem with decent management in clement climates. $\endgroup$
    – AlexP
    Jul 19, 2018 at 12:12
  • 1
    $\begingroup$ @Renan: No time right now, and this is pretty much the rule of thumb for low-tech agriculture. Actually if they really know what they are doing they could get by with even less land... $\endgroup$
    – AlexP
    Jul 19, 2018 at 12:16
  • 2
    $\begingroup$ 4½ acres per person using 21st century practices is an all-inclusive average for the USA. There's been a number of identical questions asked in the past 6 months, so this topic has been explored from several angles with variations based on levels of technology and knowledge available to the farmer. $\endgroup$
    – pojo-guy
    Jul 19, 2018 at 12:22
  • 2
    $\begingroup$ Minecraft Skyblock, anyone? $\endgroup$
    – Dubukay
    Jul 19, 2018 at 15:56
  • 4
    $\begingroup$ they will need lots more calories maybe 6,500 EACH, this is the amount for a rural worker. dailymail.co.uk/femail/food/article-3373086/… $\endgroup$
    – WendyG
    Jul 19, 2018 at 17:16

6 Answers 6

20
$\begingroup$

Biosphere 2 was an attempt at doing this sort of experiment. It was a 3 acre enclosed structure, crewed by 8 humans who would grow all the food they would eat, as well as all the oxygen they needed to breathe. Part of this was to establish what sort of size environment would be necessary for long term space colonization/travel. Most of their activity each day was tending to crops. For a colony space ship, living this close to the edge would mean disaster if more than a small percentage of people in your crew got sick or were otherwise unable to be subsistence farmers.

The goal is to survive indefinitely with good health. Decades at least.

For this goal, I would aim for 5 acres (2 hectares) per person. And aim for a permaculture setting where you have multiple types of crops (so a rust/insect that wipes out one crop one season will not wipe out the rest of your food). Keep in mind the Irish Great Famine, where most of the farms were of the size we're considering here.

Does it make sense to plant homogeneous crops or strive for diversity?

Aim for diversity. Many Native American tribes cultivated a combination of maize, beans and squash. This was called "the three sisters".

In 1845, 24% of all Irish tenant farms were of 0.4–2 hectares (1–5 acres) in size, while 40% were of 2–6 hectares (5–15 acres). Holdings were so small that no crop other than potatoes would suffice to feed a family. Shortly before the famine the British government reported that poverty was so widespread that one-third of all Irish small holdings could not support their families after paying their rent, except by earnings of seasonal migrant labour in England and Scotland.

The potatoes in Ireland were genetically clones of each other. A disease that affected one plant affected them all. The book Altered Harvests goes into details about this and the US Corn Blight in the early 1970s.

$\endgroup$
1
  • $\begingroup$ The three sisters were a great combination. Not only that it complements each other, the 3 crops is pretty nutrient rich combo to sustain someone. $\endgroup$
    – Sonvar
    Jul 16, 2019 at 4:36
14
$\begingroup$

In the Uk there was a woman called Hannah Hauxwell, she was famous in the 70's and 80s for living self sufficiently on a smallholding in Yorkshire. her lifestyle was in no way lavish and she had 15 acres. but she didn't produce her own material for heating. or produce her own linen for under clothes (she would produce wool). But this was hard yorkshire pennines land.

http://www.dailymail.co.uk/news/article-3537770/Remote-smallholding-stoic-farmer-Hannah-Hauxwell-lived-survived-170-year-iconic-1970s-documentaries-goes-sale-590-000.html

In Elizabethan (UK) times there was this act: https://en.wikipedia.org/wiki/Erection_of_Cottages_Act_1588

The Erection of Cottages Act 1588 was an Act of the Parliament of England that prohibited the construction - in most parts of England—of any dwelling that did not have at least 4 acres (1.62 ha; 0.01 sq mi) assigned to it out of the freehold or other heritable land belonging to the person responsible for its construction.

This was considered to be the minimum land required for a serf to live upon producing their own food. but once again does not cover fuel or clothes. this allowed the keeping of a few animals, and growing of vegetables. And another caveat they would have had common land to graze their animals upon.

$\endgroup$
2
  • 5
    $\begingroup$ That much land would support the serf with his whole family, though, I think. For one person, 4 acres would be plenty. $\endgroup$
    – workerjoe
    Jul 19, 2018 at 17:25
  • $\begingroup$ it was for whole family yes. $\endgroup$
    – WendyG
    Jul 19, 2018 at 17:29
2
$\begingroup$

My wife did a project for one of her agriculture classes at the University where she had to plan out a farm for one family to live on using the minimal amount of land to still get them all their calories and nutrition. The plan was for just 1 acre. I don't remember but I think that did not include the dwelling space. And it was just enough calories to survive. So it would have been subsistence living.

$\endgroup$
2
$\begingroup$

According to The Institute for Innovations in Local Farming, it seems that 1/2 acre should be sufficient. The feasibility study they did in 2007 was aimed more at economic feasibility and used lands surrounding Philadelphia Water Department facilities

STF [Sommerton Tank Farm]had slightly more than ½ acre of growing space planted three to four times annually with 60 different vegetables. Another ¼ acre was used for pathways, parking, and farm structures (processing station, storage shed, portable toilet, and cooler). From a 2003 start-up, STF operated stably from 2004 to 2006 with a full-time wifehusband farmer team aided by part-time labor or a part-year assistant farmer. Aiming to achieve sales of 50,000 [dollars] in five years, STF grossed 52,000 in its third year [and] 68,000 in the fourth.

$\endgroup$
2
  • 5
    $\begingroup$ The goal of STF was to make a small farm that was financially self-supporting, not self-supporting for food needs. Crops were selected for a high profit margin, not for high calorie density, and the farmers obtained most of their food from the local supermarket. $\endgroup$
    – Mark
    Jul 19, 2018 at 21:29
  • $\begingroup$ This has good information, but does not answer many parts of the question. Look at the last paragraph of the question. $\endgroup$ Jul 20, 2018 at 0:25
1
$\begingroup$

I would say the land needed would depend on what materials you are planning on giving them access to. As earlier answers have stated, if they will also be growing things like hemp they will need more land.

I can answer with certainty though, that a monoculture would be an extremely poor choice for the person in this scenario. Planting the same crops over and over is the fastest way to deplete the soil of the required nutrients for that plant.

Crop rotations provide a way for the soil to recover. An excellent example is a corn/soybean rotation seen throughout much of the midwest. Corn is an intense user of nitrogen. Soybeans use less nitrogen, and a certain amount of that can be taken directly from the air thanks to a bacteria that forms on the roots of the plants. This off year is vital to allow the nitrogen to replenish.

Also, in such a small area, I am of the opinion it would be important to have a diverse enough rotation to allow at least 2 years in between planting the same crop if possible. In such a small area, moving crop A to a different side of the plot would hardly be an impediment to any insect pests. Some insects and fungal pathogens can lie dormant in the soil for over a year. Being able to switch crops if certain pests are becoming problematic would be important.

Finally, assuming these perfect conditions, planting a diverse range of crops can even help with something as basic as weed control. To use the midwest again, our monoculture has led to problems with a certain amount of key weeds. If there was more crop rotation, and therefore a different time when the soil was bare each year, different weeds would be growing. Hence, the same set of weeds would not always be cultivated each year.

$\endgroup$
0
$\begingroup$

What your talking about I think, is called "high intensity agriculture". A complex ecosystem requires so many different inputs and produces so many different outputs that even a small scale farm is really not a small scale farm. It is managed in parallel by one person maybe, but it is really a small part of a big farm. That is if your talking about a fully closed cycle system.

Closed cycle agriculture is the brass ring for permaculturists. How to make a complex system that produces the most yield; from their perspective; is a process of having as many different species as possible in the same space. The purpose is to create the highest gross biological mass possible, from which a small yield can be sampled for the farmer. These farms look totally different than conventional farms, and their core is managed typically around a forest ecosystem.

Other approaches that produces high yields per acre are variations on aquaponics, and also insect farms. With probably insect farms being the most practical for low skillset farmers, due to the reduced number of inputs required.

$\endgroup$

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .