How To: Calculate What You Eat In A Year
When you grow your own food, you’re growing your own raw ingredients. And you’re accepting that the raw ingredients are most accessible in-season — in other words, there are no fresh strawberries in October, no zucchini in December, and no asparagus in August. It means eating seasonally. It means preserving foods when there are surpluses (hello, August) so that you have them when nearly nothing is growing (ugh, February).
This can seem overwhelming when you start. How could I possibly grow enough onions? How do I make ketchup? How do you eat fruit in January?
It’s really not that bad. It just requires a little forethought. Think of it as the ultimate meal prep.
Save Your Grocery Receipts
Before we got serious about growing as much of our own food as we possibly could, we saved all of our grocery receipts for an entire year. It’s telling, especially if you also keep rough track of which of those bought foods you actually ate. How many bags of apples did you buy last year? Did the broccoli always rot in the crisper drawer before you could eat it? Do you never have spaghetti sauce in the pantry when you want it?
Simply keeping track can teach you lots about what you eat, and how much of it. If every Friday night is pizza night, then you know you need fifty-two meals per year, minimum, requiring all the ingredients needed to make pizza.
Be Honest About What You Actually Eat
One of the worst things to do when you start growing food is to grow something you don’t like to eat. If you hate zucchini, for the love of God, don’t plant it. You will regret it with a capital R. Even people who adore zucchini regret planting it. If your kids won’t touch green beans, don’t plant 48 plants. If you’ve never eaten a brussels sprout in your life, your first year of gardening is not the time to try it out.
Experiment later. At first, grow what you know you like and will eat. If you have a salad every day for lunch, grow lettuce, spinach, swiss chard, kale, or whatever other green you like. If your kids would eat potatoes for every meal, grow potatoes. If you love polenta and cornbread, grow corn.
Do the Math
Don’t be scared! This is minor math, I swear — and I am an English major, so trust me. If it were complicated, I sure as hell couldn’t do it.
Some plants give essentially a 1:1 yield of food. If you plant one onion seed or set (the term for a tiny onion bulblet), you will harvest one onion. One carrot seed will result in one carrot. One cabbage seed will result in one cabbage. Most root vegetables and some other vegetables (cabbage, corn, iceberg lettuce, bok choy) essentially have 1:1 yields. Other plants produce multiples of edible fruit (like brussels sprouts, beans and peas, tomatoes, squash, cucumbers, peppers, eggplant, and most leafy vegetables — kale, leaf lettuce, orach, spinach, tatsoi, chard, and the like).
There are two ways to calculate how much to plant per person in your home.
First is the rough number of plants per person (i.e., 1 cucumber vine per person, or 30-50 corn plants per person). This is a good way to make a rough estimate without messing with the vagaries of harvest quantities, and it’s typically the way I roughly estimate how much food to plant.
Second is to calculate harvest per person based on a given plant’s average yield (i.e., the average tomato plant yields 8 pounds per plant). This is more specific, but not totally. Beefsteak tomatoes have a different yield than cherry tomatoes, and any individual tomato plant may produce more or less. You can do a web search for any given plants’ average yield. I would also recommend the book The Family Garden Plan by Melissa K. Norris.
No matter which way you go, it’ll probably take a few years of experience and practice before you really get the hang of what works for your family: how much you eat fresh, how much you preserve, how much you give away, how much you throw out each year. That’s OK. Take the time to figure it out for yourself.
For what it’s worth, I can give you a rough idea of what we grow each year to feed myself and my husband through the entire year (counting fresh, preserved and gifted food), as well as other uses (for instance, livestock feed or use in various crafts):
Alliums — 40 perennial onions, 40 elephant garlic, 40 regular garlic, 72 annual onions (this is not a magical number; it is simply the size of one whole seed tray), 40 leeks
Herbs —1 chive, 6 rosemary, 1 oregano, 4 genovese basil, 4 tulsi basil, 2 nunum basil, 4 parsley, 4 sage, 6 lavender, 3 rose, 1 lovage, 1 valerian, 10 dill, 4 thyme, 3 mint (here I mean types of mint, because mint spreads; I grow apple mint, peppermint and strawberry mint), 50 saffron crocus, 2 calendula, 4 chamomile, 4 St. John’s Wort
Perennials — 2 rhubarb, 6 asparagus, 2 cardoons, 4 artichokes, 8 black raspberry, 2 black mulberry, 10 blackberry, 8 apples, 2 pears, 1 cherry, 2 hardy kiwi, 6 blueberries, 4 elderberry, 30 Jerusalem artichoke, 3 horseradish
Greens — 20 chard, 50 leaf lettuce, 15 spinach, 8 arugula/wild rocket, 20 mizuna, 20 tatsoi, 40 bok choy, 20 komatsuna, 20 mustard, 20 orach, 40 radicchio, 20 Italian chicory
Brassicas — 50 kale of various types (I grow lacinato, russian red and thousandhead), 12 savoy cabbage, 12 green cabbage, 12 red cabbage, 12 brussels sprouts, 12 broccoli, 12 cauliflower
Roots — 20 radish, 200 carrot, 50 red beet, 50 golden beet, 24 rutabaga, 12 turnips
Nightshades — 42 tomatoes, 2-4 eggplant, 6 jalapeno, 4 sweet pepper, 4 cayenne, 2 tabasco, 8 sweet potato, 15 potato
Legumes — 10 pole snap beans, 50 pole dry beans, 40 shelling peas, 40 snap peas, 20 lima beans
Cucurbits — 4 cucumber, 2 melon, 4 winter squash/pumpkin, 1 gourd, 2 zucchini, 2 yellow squash, 1 white patty pan squash
Other — 4 okra, 6 roselle, 200 corn, 4 ground cherry, 20 florence fennel, 40 quinoa, 200 wheat, 20 sunflower
This seems like a lot (and it is, sort of), but it doesn’t take up nearly the amount of space you’d think. All of these plants grow on one-quarter of an acre for us. Part of the secret is companion planting (as an example, leafy greens growing in rows between root crops — all of them sharing the same space) and part is succession planting. For instance, I don’t grow 42 tomatoes at once. I grow about 30 from April to July. After those give into blight, I put another batch in the ground and they produce through October. This staggers my harvest, making it more manageable and ensuring I have fresh tomatoes over a longer period. I do something similar with peas, beans, brassicas, greens, and root vegetables.
My perennials, herbs and fruits are scattered across our property, most placed among flowers and shrubs in “decorative” flower borders. Only a few actually live in the proper vegetable garden, and they reside along its edges.