My story is set in a sort of apocalyptic world, the main characters live in an old house and they’re too afraid to go out as there’re creatures hunting them. They obviously still need to eat so my question is what kind of fruits, vegetables, roots, or just anything edible at all, can they grow inside a house with very little resources?
My money is on potatoes, for the following reasons:
- They are sturdy plants with a good output. From Wikipedia:
According to conservative estimates, the introduction of the potato was responsible for a quarter of the growth in Old World population and urbanization between 1700 and 1900. In the Altiplano, potatoes provided the principal energy source for the Inca civilization, its predecessors, and its Spanish successor. Following the Spanish conquest of the Inca Empire, the Spanish introduced the potato to Europe in the second half of the 16th century, part of the Columbian exchange. The staple was subsequently conveyed by European mariners to territories and ports throughout the world. The potato was slow to be adopted by European farmers, but soon enough it became an important food staple and field crop that played a major role in the European 19th century population boom.
They are nutritious. Wikipedia also compares it to other staple foods, and while they not the ones with the most of any given nutrient per portion, they do have a relatively good amount of vitamin C while being comparatively low on carbs and fats (as in they have less carbs per weight than rice, but please notice they are still really high in carbs anyway).
They are DELICIOUS. You can boil'em, mash'em, stick'em in a stew. They are also very good in french fries format, which is healthy because cooking does not kill all germs (to be really healthy, take this with a grain of salt).
While potatoes are really good, don't rely just on them. Ireland learned this the hard way once due to a potato blight.
Also, to really meet their nutrition requirements in the long run, your people will need to vary the plants they eat. A house may not provide adequate environment for maize (corn), wheat and specially soy and rice. They will need some fields for those.
There is a novel called The Martian, which was also made into a movie starring Matt Damon. It is about an astronaut/botanist stranded in Mars, surviving alone on a diet mostly based on potato. The book aims to be as scientifically correct as possible and is really pedantic about every tiny scientific detail. The rocket science and chemistry in the novel are precise and correct, but the fact that the protagonist survived for months on potatoes alone is the one thing that is off in that book.
A different way to get calories. An old house might have a wine cellar. A bottle of wine has about 700 calories and safe water. People do live on wine. The depicted wine cellar must have several hundred bottles which would be enough for months. If there is some hard liquor that has even more calories - maybe 1600 kcal / bottle. I think you would need some water with that but the scotch should kill any germs if you leave them together for a minute or 2.
The living on liquor angle also potentially makes things scarier for your story. Drunk people can be more emotional, or have lapses of judgement, or perceive things in an altered way. If they run out of liquor they will have withdrawals and that would be really scary.
A wine cellar is not going to sustain you for years. I cannot think of anything that could provide adequate calories able to grow in the area provided by a house, with no outside inputs except sun. We need a lot of calories; especially me. If it could be done I think people would be doing it all over the world.
You need to decide how strict you want to be on the 'inside the house' part. If you don't have some fancy green house or halls with a lot of artificial light, you can't really grow any plants indoor in sufficient quantities to feed people. In that case your best bet would be mushrooms which will grow well in any damp dark cellar. It's hard to make a balanced diet out of that.
If you are willing to handwave that, I would recommend a combination of rice and soy beans. This is a historically well proven combination that already gives you all nutrients that humans need in significant quantities. Supplement with a small amount of salt and you are essentially good to go. Note that you need a few hectar of farm land per person to grow enough to feed them.
Potatoes are a good choice if you ask me. Same with yam and ube. Make candy out of ube you can.
Also, since I live in Alaska, you can grow raspberries, strawberries, blueberries, and blackberries indoors. I hear people do this.
The part where potatoes are grown on Mars is one of my favorite parts of the movie "The Martian".
In your scenario, is there still running water and electricity? If so, there are many plants that we can grow in our homes. There are types of cucumber and tomatoes are rather simple.
There are home hydroponic setups like the aerogarden, but those grow herbs and spices, and a few small salad ingredients, nothing substantial.
You might have your character be someone who is already growing marijuana in his basement with grow lights, so he just has to add some variety to his crops!
I agree with the answer that potatoes are going to be a good vegetable to grow. However, as pointed out, it only provides carbohydrates- no protein or fat.
depending on how you define "grow" i think it's worth raising chickens in the house.
If you raise a few chickens you'll have a supply of eggs. Plus if you let some eggs hatch and raise new chickens, you can eat the older chicken and get some meat.
You can use the chicken dung to fertilize the potato crop, thus both adding nutrients to your crop as well as disposing of the waste.
and if you create a compost pile of the dung to break it down, you'll end up with worms and bugs which will be more food for the chicken.
I live in warmer weather (it only occasionally reaches to freezing in winter) so my suggestions may be tainted by that background.
Also, I think it stands to reason that a variety of corps would be more beneficial from a nutrition and also crop seasonality standpoint. One would obviously have to incorporate storage techniques like fermenting, dehydration, and cool storage to preserve a part of the in-season overproduction for leaner times.
I am thinking that it would be really useful to have access to a flat roof space (like a commercial building rooftop) where they would, amongst others, have
- access to sunlight
- growing space
- space for greenhouses
- space and ventilation for livestock e.g. chickens or pigeons
- space and ventilation for a composting operation, which may (probably should) include a way to treat/recycle human waste (urine, feces)
Otherwise, if your old mansion has a lot of balconies, especially towards the sun, these will come in handy for the same reasons. Or sunrooms/large windows, which will double as greenhouses.
I hear the potato proponents, but in warmer weather sweet potatoes are a better option: they are more drought resistant, one can also eat the shoots and leaves (which are poisonous in the potato), and (arguably) are slightly better nutrient wise. Be aware that both crops need a lot of space. Even though both are touted to be some of the most nutrient-dense crops per ground area covered. Also keep in mind that potatoes (and root crops in general) are slow-growing, so while it may be a good long-term sustainability option, for the first 3-5 months there won't be much to eat. On the positive side they can be made to store well for 6-8 months with just a little labor and know-how.
Since your setting is space-restricted, your gardening would probably rely heavily on plants that use vertical space: think vining crops like (some varieties of) squash/melons/cucumbers, beans, peas, tomatoes, etc. One related concept you may want to read up on some in this regards is the so-called Food Forest, which combines plants at different heights in the same space to use the soil to its maximum potential; the plant interaction often has mutually beneficial effects too. Up to 7 "layers" are often defined, obviously some won't be possible in your setting due to space constraints and time needed to establish:
- trees (fruit and nuts)
- vines (as mentioned)
- scrubs (berries)
- perennial vegetables
- ground covers (e.g. strawberries)
- root crops ([sweet] potatoes, beetroot, carrots, onions, ...)
Do note however that one of the main limiting factors would still be light: all leaves need sufficient light even up on a wall or in a tree. "Light in" is pretty much proportional to the amount of "food out".
Another way to make use of vertical space, would be to have tiers of hydroponics/aquaponics/vermiponics channels mounted on walls.
And remember, for all vertical/wall-mounted growing systems above, you would not be limited to inside walls (depending on your type of monster). Systems mounted high enough on outside walls to be out of reach of monsters will create a lot of space and access to sunlight. The characters will need some pre-existing or jury-rigged walkways to access them, though.
I've mentioned pigeons. So plant food could be supplemented from birds such as these that could be caught by the inhabitants. Another way to supplement plant food would be through Entomophagy, in other words, Insects as food.
How much space do you need?
This obviously depends on a lot of factors (like light, water and temperature) and thus no two sources agree. I'd say you could get away with around 2m² per adult for year-round production under conditions including:
- maximum soil fertility, which can be improved with additions of earthworm compost, bone meal and other nutrient sources, the targeted improvement of microbial/fungal soil activity, mulching, and a minimum-till approach.
- (healthy soil like this that produces healthy strong plants will also do much to avoid plant diseases and pest insects.)
- multi-tier production like in the Food Forest concept, or similar.
- efficient recycling of nutrients back into the soil.
- optimal light, moisture, temperature.