Everyone loves a garden. Growing plants is good for mental health, and helps us stay active and enjoy the outdoors. But this book is focused on regular people getting through hard times – and that means having goals that are achievable.

Making tough times better requires us to stay clear-sighted. In the case of gardening for food, we need to make sure we understand what we can and can’t grow and how that impacts our plans.

Imagine this – a hospital has the medicine for a rare illness stored in a cabinet. It’s locked until it’s needed. One day the illness has an outbreak with 10,000 people sick and they open the cabinet and find there are only 50 doses of medicine inside. By assuming the cabinet had everything they needed, they made a bad situation worse. Maybe with some planning those 50 doses could have been stored just for if an infectious disease doctor got sick. The first infection would have been their sign to order many more doses for the general population.

Knowing in advance what problems you can and can’t solve by yourself helps you use those resources carefully and know when to ask for help. For gardening, we can learn what plants we can grow, how much we can expect to harvest, and what food we’ll still need to get from stores and other people.

This text is not a guide to farming – people write enormous textbooks and develop university programs devoted to the subject, and still don’t describe everything there is to know. Instead we want to give you a brief orientation to growing food, along with some initial ideas to get you going in the right direction. 

Staying Realistic – Why Most People Can’t Feed Themselves

Chances are, you live in an urban area. 4 out of 5 people in the US live in a city or nearby suburb. Unless you are that 1 in 5 people, relying on a garden as a main source of food won’t work for you. This is a hard truth.

Unfortunately, many people incorrectly assume a small amount of and a hard working gardener could feed a family if times got tough. Growing food is labor intensive, and each square foot of soil can only produce a limited amount of harvest. There’s a lot of up front investment necessary – either in time or money. 

In the most advanced mechanized farms, full of tractors, expensive fertilizers, and skilled full time laborers, the most amount of calories on record in a single harvest is around 16 people fed per acre (16 million calories). One square mile is 640 acres, which would make just over 10,000 people fed per square mile of corn field. 

Looking at this map of population density in the USA, we can see that most cities and suburbs converted 100% to corn farming (no buildings, roads, forests, or parks), would be unable to feed the current population density.

We’re able to support these dense cities by having lots of the USA devoted to just growing food without many people living there. That means cities only work when people are able to buy food rather than grow it for themselves.

For those who want to commit to growing their own food (instead of relying on farms, markets, and stores) it’s important to have realistic goals and put in the time and effort on building up skills that will be worth the investment.

If your local landscape has more than 10,000 people per square mile, it’s impossible to grow enough food to feed everyone. If you yourself don’t have access to at garden of at least 50’x50′ (1/16th of a square mile) you can’t grow enough food to feed just yourself, even if you had all the tools a modern farmer uses.

Why grow food?

If the majority of people can’t grow enough food to feed themselves, what’s the point of running a garden?

As we discussed in the Nutrition 101 section before, we can break down food into a few essential components:

• Energy – what you need to not starve to death, measured in calories. This is what we talk about when we say how much food we need to feed ourselves.
• Macronutrients – the basic building blocks of your body and the largest part of your diet. These nutrients are what your body burns to produce calories, and are called protein fat and carbohydrates.
• Micronutrients – vitamins, minerals and other trace nutrients. Without these, you will begin to weaken and get sick, develop disabilities, or die.

With that in mind, we all know humans get more from food than just raw nutrients. People relate to food with a range of psychological and emotional dynamics, and often derive personal meaning from their meals. These often include:

• Satiety – feeling full and without hunger. This is incredibly important for quality of life and morale. Usually this is through fiber, but fat and other nutrients play a role too.
• Enjoyment – well being and happiness we get from good food. This also includes cultural connection, and the emotional satisfaction we get from feeding the people we love.

These 5 components are a useful way to think about how we relate to food production. Although all are essential to living a good life, some are more important for survival.

For people who are lucky enough to live in an area that could produce an abundance of calories, they are in a position to serve as the keystone of a larger group of people. They could be the engine that powers communities. This is basically how the USA works now – with farms like those in the Midwest feeding the cities across the country. At a smaller scale, during hard times people near open land could be supplying food to folks living in areas of denser population.

In the USA the majority of folks are not in these rural situations. Instead, they should be considering which of these other components of food they could be either be meeting or contributing towards through growing.

Regardless of circumstance, it’s good to approach gardening step by step to increase your abilities and capacity. This is the path we recommend for most folks:

1. Enjoyable foods – most people can grow food that can improve their quality of life, even in a window or balcony. It teaches good lessons about raising plants, and many herbs and spices are fairly easy to grow. 
2. Micronutrient sources – with a small kitchen garden it’s possible to grow many micronutrients which are important for maintaining health. Increasing the space to grow, developing gardening skills, and learning about food storage and preservation, steadily increase this capacity.
3. Increased satiety – more fiber in meals means more plants need to be grown, with veggies in every meal all year long. This means dedicated space for vegetable storage, a large garden, and high skill in plant cultivation.
4. Macronutrients – specializing in very specific plants is necessary to meet macronutrient needs. ?Typically this is in the form of staple crops in very large gardens or orchards. To reach peak capacity it can take years to develop soil, improve infrastructure, and establish perennials like trees and shrubs. 
5. Energy – You need a farm to get all of your calories. The farm can be quite small – though a few acres is enormous for non-rural people – to meet these needs, but it requires the same degree of dedication. You’d likely also need specialized equipment and machinery, and multiple people working the farm full time. Note that this doesn’t mean a family is self-sufficient – normally farms are cooperatively operated, and still import many resources from neighboring communities. 

As you can see, each step provides more resources than the last, and leads to greater degrees of capacity and skill for resilience. They also demand more resources, time, and labor. This means that most people will never reach the ultimate goal of growing all their own food, but whatever step they stop on will be better than the one before.

Crop Profiles

In the following section we’ll dive into some specific plants we feel are worth highlighting for their nutrient profiles. Each section starts with a heading like this:

Spinach

• Time to Harvest: 8-12 weeks
• Seed Sprouting Soil Temperature: >40°F
• Cold Kill Temperature: 15°F
• Heat Kill Temperature: 75°F
• Ideal growing temps: 50-60°F
• Excellent source of:  Folate, Vitamin A
• Good source of: Calcium, Iron, Vitamins B1, B2, B3

This heading contains information designed to help you make decisions about what to grow.

Time to Harvest and Temperatures

Like animals, most plants have a window of temperatures they can happily live in. They also have other temperatures further outside that window where they can survive but not grow well – this is similar to when we can’t do exercise because of heat and humidity, or we’re shivering uncontrollably because of the cold. We call the band of good temperatures the ‘ideal growing temperature’. By knowing the time from planting to harvest, and the ideal temperatures, you can figure out if a plant would do well in your local conditions.

There is also an upper and lower bands of survival – these are temperatures that actually risk killing the plant. If your region has dips above or below the ideal growing temperatures, but avoid hitting the upper or lower limits, the plant can be alright. Remember that these times outside the ideal but not quite killing can pause all plant growth – so if they become common, the plant may not mature enough to be harvestable. 

Nutrition Sources

In prior sections we talked about common nutrient deficiencies in times of scarcity. Those nutrients that frequently were missing – Vitamins A, B1/B2/B3, Folate, Iron, Calcium, Protein and Fat – are the ones we highlight good and excellent sources of here. A good source means you get >10% of your daily need from a serving (usually around a cup), and an excellent source provides 20% or more.

Remember that these nutrient amounts are just estimates, and everyone’s body is different. Most plants also have a range of nutrients in small doses, so a diverse diet can help a lot if a good source of a specific nutrient isn’t available.

Seed Sprouting

Unlike mature plants, seeds require conditions to be just right in order to grow. Although an adult plant can handle more extreme heat or cold, a seed will refuse to sprout if the temperature or moisture aren’t perfect. This means you may have soil full of seeds and no baby plants even though it’s warmer than the killing temperature.

If we imagine a cool weather plant (like carrots) and their view of the seasons in someone’s garden, it might look something like this:

The cold winter months are deadly, but then become non-ideal cold weather, before shifting into a block of ideal temperatures. This eventually becomes hot, and then deadly hot weather, before the cycle reverses.

If we zoom in on just the spring months, we’ll see a window of time where the plants are in ideal conditions for growth, and how long that time will last.

This 2 month window is the amount of time a cold weather crop has to mature in our example garden. Multiple harvests are possible with plants that take 1 month or less to mature, and plants that take the full 2 months might be at risk of never ripening if the summer comes unseasonably quickly.

With all this in mind, we can look at different plants’ ideal growing conditions and time to maturity and see which plants might be suitable for our gardens – both now and in the future as the climate continues to change. Remember, just because we love a vegetable or if people think it’s ‘easy to grow’, it doesn’t automatically make it a good fit in our dirt.

 

Fast Calorie Crops (Harvest within 7 weeks)

For the purposes of this list, we’re going to define ‘fast calorie crops’ as plants that can be harvested in under 2 months and have some real , instead of just leafy greens (which are generally faster to grow but lower in calories). 

Turnip

• Time to Harvest: 6-10 weeks
• Seed Sprouting Soil Temperature:
• Cold Kill Temperature: 10°F
• Heat Kill Temperature: 80°F
• Ideal growing temps: 40-75°F
• Excellent source of:  Root: none | Leaves: Folate, Vitamin A
• Good source of: Root: none | Leaves: Calcium

Turnips are the king of fast crops. They’ve been used as a staple in northern Europe, especially in regions with cold weather and short growing seasons (like Russia and eastern Europe). Cold temperatures in the early spring and late fall don’t kill these plants once they’re established (but seedlings are more sensitive) which makes them an ideal crop for stretching growing into the cold seasons.

The early varieties can be harvested in just over a month, making them the fastest way we’ve found to produce meaningful amounts of calories. The tops are also edible and commonly eaten sauteed with bacon and butter. This makes turnips a dual-crop that produce both a starchy root like a potato, and nutritious green to be eaten as a side dish.

Radish

• Time to Harvest: 3-5 weeks
• Seed Sprouting Soil Temperature:
• Cold Kill Temperature: 20°F
• Heat Kill Temperature: 80°F
• Ideal growing temps: 60-65°F
• Excellent source of:  none
• Good source of: none

Radishes are similar to turnips – they are a fast root vegetable with edible greens. However, radishes are slightly less nutritious (closer to lettuce), and require a tighter temperature range to grow successfully – in the wrong conditions they will not swell their roots or become palatable.

This means they are a wonderful supplement to turnips but are not the main calorie crop in any established food systems.

Bush Beans

• Time to Harvest: 7-9 Weeks
• Seed Sprouting Soil Temperature:
• Cold Kill Temperature: 40°F
• Heat Kill Temperature: >100°F
• Ideal growing temps: 65-85°F
• Excellent source of:  Folate
• Good source of: Protein, Iron, Vitamin B1

Bush beans are a warm-season crop that produces fairly quickly, while also providing more protein and a different mix of micronutrients than cool season root crops. The pods can either be picked while still green but with plump beans inside, or you can wait until they dry out to remove the beans from the pods for long term storage. The dried mature beans are very nutritious – unlike the green pods – but require waiting longer to harvest.

Pole beans are similar to bush beans, but require a few more weeks to mature and climb up on vines instead of staying low to the ground. However, pole beans continually produce after you harvest – bush beans produce a single crop and then slow down or stop.

High Calorie Crops (120’x120′ harvest feeds 2+ people)

In this section we define high calorie crops based on the amount of food which can be produced in a single harvest. For a sense of scale – 1 acre of corn can provide enough calories to feed 15 people all of their calories for a year (15,000,000 calories), meanwhile an acre of spinach can only feed a person for about a year and a half (1,669,220 calories). We graphed out the caloric values of many food plants and found that there is a line at around 6,000,000 million calories per acre where foods begin to be seen as a primary food source (like rice, wheat, corn, or potatoes) by the people who grow them.

We chose 120’x120′ to represent a large garden that could be managed by a single person – each side is about as long as 3 school buses lined up. That’s about a third of an acre, which means we’ll be listing plants that can feed about 2 people from this imaginary garden in a single harvest.

We’re also only listing plants which don’t require a lot of processing, because this is a guide about hard times where harvest machinery or hard labor could be hard to come by. Traditionally many of nutritious staple crops were laboriously processed using lots of grinding and thrashing and other difficult steps. This includes wheat, rye, oats, and rice. We include 2 crops which require some effort (sorghum and amaranth) because the amount of labor is still fairly low. Root and large fruit crops will always be less work to process and so they’re our primary focus.

Rutabaga

• Time to Harvest: 12-15 Weeks
• Seed Sprouting Soil Temperature: >40°F
• Cold Kill Temperature: 12°F
• Heat Kill Temperature: 80°F
• Ideal growing temps: 50-65°F
• Excellent source of: none
• Good source of: Vitamin B1

Rutabagas are the only true cold calorie crop on our list. Able to survive extremely cold nights and spring warm spells (but preferring mild days), it is an adaptable and reliable way to get fed. 

During the famines in WWII-era europe, rutabagas got people through the hardest of days. Unfortunately this has led many to consider the plant a ‘famine food’, despite it having a mild sweet taste similar to a potato. People still eat rutabaga in dishes that have other starchy root vegetables like carrots, turnips, beets, and potatoes.

Potato

• Time to Harvest: 13-17 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 28°F
• Heat Kill Temperature: 100°F
• Ideal growing temps: 60-70°F
• Excellent source of: Folate, Vitamin B3
• Good source of: Protein, Iron, Vitamins B1, B2

Potatoes are one of the greatest achievements of the Incan farming traditions. Researchers have found it is one of the only foods that is (almost) entirely complete nutrition – people have survived on eating only potatoes for months or years with limited negative effects (and some positive ones). Potatoes only lack a few trace vitamins and minerals, and the fat needed to absorb them. That means mixing potatoes with some greens and a fat such as butter, olive oil, or lard, will give you complete nutrition.

Plus, potatoes are extremely filling. Unlike other foods which your body processes quickly, potatoes both fuel you and make you feel like your stomach is full. Like other members of the nightshade family, potatoes contain a toxic chemical called Solanine. This is why only the tubers should be eaten and those must be cooked.

Sweet Potato

• Time to Harvest: 13-17 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 55°F
• Heat Kill Temperature: >100°F
• Ideal growing temps: 85-90°F
• Excellent source of: Tuber: Vitamin A Leaves: Vitamin B2
• Good source of: Tuber: none Leaves: Folate, Vitamin A

Sweet potatoes are not actually related to the true potato. Instead of being in the plant family of tomatoes and peppers (nightshades), the sweet potato is in the morning glory family. This becomes more obvious when you look at their leaves and flowers which look very different from one another.

As a true tropical plant, sweet potatoes thrive in hot weather and struggle as the days become cool. Depending on your region this plant might survive multiple years, or only make it through the middle of summer. 

Similar to some of the other veggies we’ve discussed so far, sweet potato greens are edible and used in many traditional cuisines. The leaves can also survive being walked on (but not stomped on) and thus are great plants to put in dirt walkways that don’t get a lot of foot traffic or running kids.

Sweet potatoes are an excellent source of vitamin A which is normally found in dark green veggies. However, this can be harmful in very high doses. You probably shouldn’t eat more than one per day.

Pumpkin

• Time to Harvest: 13-17 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 50°F
• Heat Kill Temperature:
• Ideal growing temps: 65-95°F
• Excellent source of: Pumpkin: Vitamin A Seeds: Vitamin B1, B3
• Good source of: Pumpkin: none Seeds: Protein, Fat, Folate, Vitamin B2

Pumpkins are a triple-duty plant. They have a starchy flesh that can be used in a variety of dishes. The skin naturally develops a protective wax which acts as a natural preservative – no refrigeration needed. They also have edible seeds which provide excellent protein, fat, and B vitamins. 

Pumpkins come in both bush and spreading vine forms. The vining types produce more, because they spread along the ground and become much larger plants. However, they can climb over and kill other plants and so need a lot of room to spread (or need to grow around tall plants like corn or sunflowers).

Similar to sweet potatoes, the high amounts of vitamin A in pumpkins are healthy, but shouldn’t be eaten in enormous doses. A few cups a day is plenty.

Amaranth

• Time to Harvest: 12-15 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 32°F
• Heat Kill Temperature: >100°F
• Ideal growing temps: 70-85°F
• Excellent source of: none
• Good source of: Grain: Iron Greens: Iron, Calcium, Folate, Vitamin A, B2

Amaranth was a food so powerful and important to the Aztecs, Spanish conquistadors banned cultivation to force the people into submission. Historians believe 80% of the Aztec diet may have been Amaranth.

Every winter around December, the Aztec people worshipped the sun god Huitzilopochtli with the holiday month of Panquetzaliztli. This end of year celebration represented the rebirth of the sun, and was spent fasting and giving thanks for the generosity of the world. The holiday finished with foot races and a meal of amaranth honey cakes shaped in the form of Huitzilopochtli which were cut up and shared. Many of these traditions transformed into Mexican Christmas festivities tolerated by the conquistadors, like Las Posadas.

Amaranth seeds are a tiny grain that are closely related to quinoa. It is a highly productive staple crop that’s similarly bountiful to European grains like wheat. Unlike wheat however, amaranth is gluten free.

The grains ripen after growing through a hot season, and can be harvested by shaking and separating the seeds ( from their casings known as threshing and winnowing) after cutting the stalks down.

The greens of the plant are also edible and are a common food (often as a cooked veggie or stew) in Mexico. Because amaranth has many wild cousins local species are eaten around the world. Callaloo (Caribbean) Efo Riro(West Africa), Note Shak (South Asia), Vlita (Greece), and Choraiya Bhaji (Fiji), Canh Rau Den (Vietnam), are just a few examples.

Corn

• Time to Harvest: 10-17 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 32°F
• Heat Kill Temperature: >100°F
• Ideal growing temps: 85-90°F
• Excellent source of: Vitamin B1, B3
• Good source of: Protein, Iron, Vitamin B2

Corn is the engine behind the world’s food supply. Civilizations and communities large and small all over the world have grown corn as their primary source of calories. There is currently no crop which outperforms corn in terms of the amount of food produced in a single harvest.

Originally from the tropics, corn is a kind of grass that loves hot weather. It has special adaptations that allow it to grow in weather so hot that other plants slow down or die (this is a special trait in certain grasses, called c4 metabolism). 

This means corn is a machine that takes the sunlight and summer heat and turbo charges itself to produce a tremendous amount of food. People have bred many different varieties, including some which grow faster to ripen in the short summers of the north.

Corn is more sensitive to factors like how far apart the plants are from one another, and how many plants overall are in the garden. This is because unlike many other vegetables their pollen is spread by wind instead of by insects like bees. So if there are not enough plants to produce pollen in the wind, the pollination will be low and the corn will not have many ripe kernels to eat. This means people dedicate a lot of space to just growing corn if they decide to include it in their veggie plot.

Sorghum

• Time to Harvest: 10-17 Weeks
• Tuber Sprouting Soil Temperature:
• Cold Kill Temperature: 32°F
• Heat Kill Temperature: >100°F
• Ideal growing temps: 85-90°F
• Excellent source of: Vitamin B1, B3
• Good source of: Iron

Sorghum is a grain crop not widely known in the USA. A close relative of corn, it too has the c4 metabolism that enables strong growth in very hot conditions. However, Sorghum comes from East Africa (likely domesticated in Sudan) and is adapted to hotter and drier conditions than corn can thrive in.

Harvesting Sorghum involves carefully shaking and hitting the grains off of the top of the stalk, and then removing the extra dry plant material that falls off with the seeds (doing this is called winnowing). This can make Sorghum a bit more complicated and laborious than other crops.

Like other grain crops sorghum can be eaten boiled, in tortillas and flatbreads (sorghum is gluten-free), and porridges. There is also a sweet variety that is used to make syrup, similar to how sugar cane and sugarbeets are used.