How much vegetable garden do you need to feed yourself: from 375 m2 to a hectare

How much vegetable garden do you need to feed yourself: from 375 m2 to a hectare

The question looks simple and it isn't. How much land do you need to cultivate so a family can eat? The answers floating around range from 375 square metres of intensive gardening to a full hectare, and the spread is no accident: it depends on whether you count only vegetables or also grain, potatoes and animal protein. That's the crux of the matter.

The most frequently cited starting point is Parades en Crestall, the method of Mallorca-born Gaspar Caballero de Segovia, who promises a highly productive and healthy garden with just 375 m2. At the other end, the deep bed system popularised by John Seymour in The Self-Sufficient Gardener: yields up to four times higher than traditional methods and, according to its advocates, between 90 and 180 kg of vegetables a year in 9 m2, when one person consumes about 145 kg annually.

How many vegetables can you grow per square metre?

This is where the serious disagreements begin. With vegetables, figures of 5 kg per m2 and even 25 kg under optimal conditions are quoted, because vegetables are largely water. With wheat, the yield drops to about 700 grams per m2, and maize comes in around 2 kg. The maths changes completely when the goal shifts from lettuce to calories.

The most striking case is the potato. One video promises 45 kg from a single square metre using the deep bed method, a figure several readers dismiss outright as fantasy. The field experience shared suggests that to harvest those 45 kg you need at least 5.6 m2 with a highly productive variety, irrigation and a dry, sunny climate; in rain-fed conditions, no less than 20 m2. The person who tested it alongside a traditional crop on the same plot sums up the result in one sentence: the yield was very similar.

Grain, the unfinished business

Covering your carbohydrate needs is another world entirely. Average consumption in Spain is around 86 kg of wheat a year per person, and with an excellent yield of 1 kg per m2 that's 86 m2 just for one person's bread. Harvesting grain by hand is also sheer torture: a combine harvester brings in around one tonne every 15 minutes. No weekend garden can compete with that.

Hence the recurring conclusion: we're not going to get wheat cheaper than buying it. For those who keep livestock, growing it can pay off, but for everyone else, buying sacks of flour is the sensible route.

Animals, fruit trees and the factor nobody controls

Animal protein is the least efficient chapter. A cow converts barely 10% of what it eats into meat; hens improve the ratio and cold-blooded animals —fish, crocodiles— come close to 100%. The practical advice is to raise only animals that make use of what humans don't eat.

Climate, water and fertiliser decide the rest. Nature is fickle: hours of sunshine, soil quality, pests and fertilisers shift productivity from one year to the next. And the manure that makes a deep bed fertile doesn't come free: it comes from keeping animals all year round, something that isn't exactly appealing today.

Is it worth it economically?

As a hobby, the garden delivers produce with far better flavour and good entertainment. As a saving, the numbers fall apart as soon as you factor in the hours, the tools and the treatments. It only adds up if your produce goes to well-off customers willing to pay for the extra care.

With these numbers, the honest answer to how much garden you need is that nobody has it pinned down. It depends on the gardener's skill, the climate, and whether bread and stew are also on the menu.