This guide walks through why calorie density matters more than variety when planning a survival garden. Most vegetables are mostly water and fiber, while beans, grains, and potatoes provide the calories a family would need to get through a food shortage. It breaks down calories-per-acre and calories-per-square-foot numbers for the high-calorie crops, explains why low-calorie favorites like lettuce and tomatoes won’t sustain anyone long-term, and covers practical considerations like growing at higher elevation, planting corn, beans, and squash together using the Three Sisters method, and how many calories to realistically expect from a home garden per person.
This article has been significantly updated by Lisa Bedford, August, 2026.
In good times, there are a dozen reasons to garden. It saves money, you spend time outside in the fresh air, it gets you closer to your food source, and it teaches your kids a practical skill. In bad times, there’s exactly one reason: to grow enough food to survive.
I used to think that meant “grow vegetables,” and when you visit homestead and gardening websites, that’s the main focus. But if survival is in the back of your mind, you need to look at gardening from a numbers point of view.
Calories Per Acre: How Survival Garden Crops Compare
Calories matter a lot when it comes to relying on your garden for survival. The thing is, not all garden crops pull their weight when it comes to calories, so there are decisions to make about what to plant because they all require money, time, and effort. To give you a starting point, here’s roughly what an acre of these crops produces:
- Potatoes: ~26 million calories per acre
- Corn: ~7.5 million calories per acre
- Rice: ~7.4 million calories per acre
- Wheat: ~3 million calories per acre
- Soybeans: ~2.8 million calories per acre
Lettuce, tomatoes, and most garden greens don’t come anywhere close to this. They’re valuable for vitamins and variety, but they can’t sustain a family through a real food shortage on their own. The nutrition and calories just aren’t there.
Most garden vegetables contain more than 80% water and then a good deal of the remaining 20% is tied up in dietary fiber that is basically indigestible material. Water will certainly help keep you alive and dietary fiber will keep you feeling full but water can be more easily gathered elsewhere and dietary fiber fullness is an illusion.
Whatever is left over is generally calories in the form of mostly carbohydrates as well as any vitamins that may be present. I don’t discount the need for vitamins but without enough calories you probably won’t make it to the point of vitamin deficiency.
When it comes to survival, calories count!
I’m not telling you to rip out your lettuce bed. It’s generally an easy crop to grow, and I grow it myself. But, for a diet that provides enough nutrition, you need all of it — fat, protein, vitamins, carbs. If you’re planning to survive on low-calorie vegetables alone, you’re in for a rude awakening, and I’d rather ruin that surprise for you now than have reality do it later.
Take lettuce and spinach as an example. In good times, these can save you a lot of money over grocery store prices. But lettuce runs about 95% water, with almost all the rest fiber. A hundred grams gets you 13 calories. Spinach does a little better at 23. I love a garden salad as much as anyone, but a salad has never gotten anybody through a real emergency.
Tomatoes aren’t much better. I adore tomatoes and love their versatility, but at 93% water and only 18 calories per 100 grams, the math doesn’t work out for someone in a food crisis. It’s kind of ironic that big vines and huge harvests add up to almost nothing in a survival scenario unless you plan to live on lycopene alone.
The whole Cucurbit family — cucumbers, melons, squash, pumpkin — tops out around 20 calories per 100 grams. Broccoli, cabbage, cauliflower, and brussels sprouts do a little better, up to 40. Root vegetables climb further: turnips at 21, parsnips all the way up to 60.
Now that I’ve ruined everyone’s favorite crops, what’s left?
The Big Three: Beans, Potatoes, and Grains
These are what I call the big three of the food crops: beans, grains, and potatoes. There’s a reason why people have subsisted on these crops since ancient times. They simply work and work well for sustaining life.
Beans
There is a very good reason that beans are the food of choice in the survival slogan, “beans, bullets, and band-aids”. In most of the world, beans refer to the kind that are grown and dried, not the green bean type, although some varieties of the green type are quite nutritious.
Simply put, beans are one component of a complete protein diet. An incomplete protein is simply one is deficient in all of the necessary amino acids to heal tissue and promote growth. A cup of cooked pinto beans runs about 245 calories, and dried, they store almost indefinitely.
Beans are also easy to store and grow. Once dry they store almost indefinitely if kept from pests, and in healthy soil, they make their own nitrogen. How? Well, being a legume means they form root nodules filled with symbiotic bacteria known as rhizobia. These bacteria take a small amount of oxygen and sugars from the plant and help make usable nitrogen. When the plant dies, the nodules fall off, leaving nitrogen in the soil.
Grains
The next part of the complete protein diet is a little harder to grow. All continents with substantial human populations have had grains growing over a large portion of the land at one time or another.
The fortunate thing is that there is such a variety in this category that finding one that grows in your particular climate and growing conditions is possible. For instance, rice likes warm flooded land while wheat likes cooler, drier land. In addition, there are the more exotic types of grain, such as quinoa and amaranth. Corn is a good grain to grow as well. Just be prepared to feed it tons of nitrogen rich matter and water.
To give you an idea of what you can count on, calorie-wise, 100 grams of wheat provides about 330 calories, more than four times what the same weight of potatoes provides, which is part of why grain has anchored so many diets throughout history, difficult as it can be to grow.
Like beans, grains are generally easy to store as well, although they might be a little more susceptible to pests.
Potatoes
Though they add little to the protein game, there is little doubt that for carbohydrates potatoes rule.
Except for the French, who considered them a dirty, common food and refused to eat them, potatoes were a staple across much of Europe for a long while. Despite the Potato Famine in Ireland (due to monoculture) they continued and still remain an important crop with a lot of variety.
The benefit of potatoes is that they grow in conditions that grain isn’t always fond of. Moist, cold conditions are no real problem for potatoes because the bulk of their energy stores are below ground. And though they fare less well in storage than the other two foods, it’s not impossible to keep a batch fresh as long as they stay in a cool root cellar.
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“Make Your Next Garden Your Best Garden” is a free printable that helps you assess your gardening strengths and weaknesses, determine which crops will be most successful for you, and decide which tools and supplies are necessities. You can request the printable here.
Calories Per Square Foot: What This Actually Means for Your Garden
Earlier in this article when I gave you calorie counts for an acre of rice, beans, and so on — the truth is that almost no one reading this article is going to plant nothing but that single crop in an entire acre. And, that’s a lot more land than most of us are working with.
It’s a tidy way to compare crops on paper, though, but let’s scale it down to something closer to a real backyard:
Potatoes is the one crop I recommend growing. Just one small patch can produce somewhere in the range of 70 to 180 calories per square foot over a season, depending on your soil and the variety you plant. You can dehydrate or freeze-dry potatoes for a longer shelf-life as well as home-can them.
Dry beans run lower per square foot than potatoes, but they store far longer and cover the protein potatoes can’t. They can’t be beat when it comes to versatility and utilizing them as a meal-stretcher.
Grains generally need more room than most home gardeners have to spare, which is part of why they’re the hardest of the big three to grow at home. However, if you are able to have success growing one or more, when it comes to shelf-life, they’ll outlast almost anything else in storage.
If gardening space is what you’re short on, go with potatoes. You can grow them in plastic bins, a straw bale, containers — you really get a lot of bang for the buck. If you’ve got acreage to work with, that’s when grains and beans start making sense in terms of money and time invested.
The Final Word
Hedge your bets, and grow a little of everything. I still have my containers of tomatoes in the backyard, and I don’t think you should give up yours. But know, going in, which crops you can actually depend on if things get hard, and which ones will leave you hungry no matter how well they grew.
Jason Akers contributed to this article, March 2018. It has been significantly updated by Lisa Bedford, August, 2026.
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Frequently Asked Questions
A very rough target would be roughly 2,000 calories a day per adult, which is about 730,000 calories a year. No home garden alone is going to get you there. Even potatoes, the highest-calorie crop covered here, would need somewhere close to a quarter acre per person to hit that number on their own. Realistically, it’s best to view a garden as a supplement to food storage, which is why the crops you choose to prioritize matter so much.
Shorter growing seasons and cooler soil change the math quite a bit. Potatoes tend to do well at higher altitudes since they tolerate cool, wet conditions better than grain does. Beans need a longer frost-free window, so check your specific variety’s days-to-maturity against your local growing season before counting on them. Grain becomes the hardest of the big three because there often isn’t enough season to finish the crop. My recommendation is to find your county’s extension office for specific crops that grow best in your area, and if this still isn’t a good option for you, focus stocking up on beans, rice, grains, and potatoes in dehydrated and freeze-dried forms and focusing your gardening efforts on veggies, herbs, and fruit that you can enjoy now and preserve the harvest for later.
Yes, and since it grows two of the big three together in the same space, it’s worth trying. Corn, beans, and squash are planted together. The corn stalks give the bean vines something to climb, the beans fix nitrogen in the soil that the corn uses heavily, and the squash’s broad leaves shade out weeds at ground level. It’s an old method used by Native American gardeners for generations, and it’s an efficient way to combine grain and beans without having to use up valuable space for each.
We see our garden as not only our food pantry but also as a teaching tool for ourselves and neighbors. Even in wide open spaces, it is not common to see a small garden. Horses seem to be more prominent and horses and gardens don't seem to go together. 🙂
This time of year (in my area) I have not found much spinach in sores. It's a common ingredient in my daily smoothies. I have learned to improvise and use what ever greens are in my garden. Lettuce, kale, collards and even cabbage greens. I have been known to blend up my kids turnip roots in smoothies to get them into my children. It's much easier for children to get nutrients this way than having a plate of turnip roots for lunch. And they get the other nutrients of the fruit and sprouts or whatever seems to find it's way into the smoothie.
Whether bad times are upon us just around the corner or during the next generation, now is the time to be educating our children (and ourselves) on proper nutrition and real foods. I believe a garden makes a perfect opportunity.
I think I will add a few extra rows for beans as well as lengthen my potato rows this spring.
Thank you for the calories vs grams illustration. I never thought of that.
you can also grow potatoes "vertically" using a stack of three or four old tires. Simply start your seed potatoes inside one tire laid on its side and filled with soil, then as the plant frows upward you add a tire and soil loosely around the green part always leaving a couple of inches of the green plant above the soil level. As you add each tire the potato plants will grow additional offshoots into the prgressively stacked tires. I haven't seen it done more than four tires high though. We keep them behind the privacy fence since my teenage daughter proclaims us the to be the rednecks on the block! She doesn't mind it too much when I make her fresh bread with homemade butter and blackberry jelly though!
Love this idea!
A few questions:
1. Do you harvest the potatoes all at once?
2. Are the bottom potatoes larger than the top?
3. Do you grow or buy your potato seeds?
I use a chicken wire frame, lined with brown paper bags split open to grow my potatoes. Yes, the paper is a mess by harvest time, but it's only there to keep the soil in, after all. I always harvest all at once, though if you use good loose soil you can sneak your hand down the edge and feel for baby ones to steal early. Yes, the ones at the bottom are usually larger, since they're older.
I have used seed potatoes and ordinary store bought ones. The certified seed actually produce better. About a quarter of the store bought ones don't sprout, and they're more likely to get blight. Certified seed potatoes are treated to avoid blight and fungi.
I buy seed potatoes at the local feed store and harvest from top to bottom over the course of several weeks, always getting the last ones in before the first freeze. We have very mild winters in east Texas and seldom see a freeze before Christmas.
It's true, in times of stress, heavy labor, or when healing a bad wound, or working in deep cold we need more calories and protein. It's nearly impossible to get high protein levels from a strictly vegetarian diet. One cup of grain plus one cup of legumes provides all the necessary amino acids for a complete protein, but only an average of 17 grams of it. There is a reason all the more primitive cultures use a lot of animal fats in their diet.
Trust me, you still need that vegetable dietary fiber, though. Your bowel habits will thank you to keep vegetables in your meals. And vitamin C is hard to get in a lot of storage foods diets. If you have questionable gum health, look to your vitamin C intake.
Great Article Thanks for some thing more to consider as I plan the garden.. cityhomesteader
Hmm….We tried corn twice in our garden. The first time the hail got it. The second time the bugs got it….we decided not to try a third time. Now that we've moved we're fond of going for drives on the weekends, and buy from some of the family farms around here that are somewhat off the beaten path. They'll sell it to you right from their porch.
As to the blending in of unknown nutrient in your kids food, its something my parents/grandparents did to me and my siblings when we were younger. And also something I plan to experiment with when I actually have a kitchen to cook in. To use April's example, just because I'm not a kid anymore doesn't mean I like having a plate of turnips for lunch. I'd rather substitute something or at least add to something in a way that I don't have to taste them….course I'm not a big fan of smoothies (or most fruits and veggies) either,but I'm working on it.
Good point about the problems of growing. IMO way too many people think growing food is simple/easy. It isn't The time and effort – not to mention the sheer size of planting needed – to provide just half the diet for an adult is enormous.
I'm glad you all found the article thought provoking. I was not aware of some of the nutrients (or lack thereof) involved until I really sat down and did the math.
@Chris–you are right, corn is tough!
Jason
While the article is thought provoking, it isn't balanced. The calories for the "bad" crops are given, but not those for the "good" crops, which would be better for the comparison. Calories and carbs are important, but dietary fiber and other nutrients provided in the low calorie crops are very important for good health, and will be even more so in coming bad times. For example, one serving of spinach, which is 180 grams, contains more than the daily requirement of vitamin A, 24% of needed calcium, 29% of vitamin C, and 36% of iron. Non-meat sources of iron aren't absorbed as well, but if you eat a tomato (149 grams) with your spinach, the absorption rate goes way up, and you gain another 32% of your needed vitamin C as well as lycopene, potassium, and several B vitamins. I'll continue to grow tomatoes, squash, and greens, but don't intend them to be my family's only source of food.
From the article:
"I don’t discount the need for vitamins but without enough calories you probably won’t make it to the point of vitamin deficiency."
100 grams of potatoes = 76 calories
100 grams of wheat = 330 calories
100 grams of pinto beans = 349 calories
You need calories to live and a variety of food to live well.
Jason
One principal that sustained many of the Native American cultures here in America was the "Three Sisters" method of planting corn, beans and squash together. The corn grows but robs the soil of nitrogen, the beans climb the corn and replenish the nitrogen, and the low laying squash acts as shade for weed control among other things. This combination provided Native Americans for generations with their nutritional needs and I have taken that concept as the foundation for my own gardening habits for both pre and post TEOTWAWKI.
Hi, I realize I’m a bit late on discussing this article – I think you make a great point on calories being our first priority in a hard times situation. However, I was wondering about which plants would be most productive in terms of space. For example, I grew pinto beans – two eight meter rows that yielded less than a kg (for all the effort involved it didn’t seem like much). I have plenty of space but for a lot of people calories per square foot might be a more important consideration?
Squash is indeed low in calories, but squash seeds are high in fat (and therefore calories)