A common question we are asked here at the Garden Planner is "How much of the food we eat as a family can we grow ourselves?" This depends on a number of factors, so here are the key things you need to consider…
How much space do you have?
The biggest factor that will determine how much you can grow is how much land you have. There are many ways to maximise the crops you can grow in any given space, but quite simply, the more land you have, the more crops you can grow. So how much land is enough for a family to grow everything they need for a year?
Research in the 1970s by John Jeavons and the Ecology Action Organisation found that 4000 square feet (about 370 square metres) of growing space was enough land to sustain one person on a vegetarian diet for a year, with about another 4000 square feet (370 square metres) for access paths and storage – so that’s a plot around 80 feet x 100 feet (24m x 30m).
How much you can grow in this space will depend on your climate, weather and soil and, crucially, how much time you have. Tending to 4000 square feet, particularly at the height of the growing season, will take many hours a week.
What would you grow and how many plants of each vegetable would you need per person?
Choose to grow plants that you already like to eat – it’s not worth putting the time and effort into growing asparagus if no one in your family is very keen on it.
Your grocery bills or a trip to a local farmer’s market are good places to start working out how much you need to grow. Create a list of plants, and note how much you eat per week – so if you eat 5lbs (about 2kg) of potatoes a week, that’s 20lbs (9kg) a month and 240lbs (109kg) a year. You’ll need to grow this amount at least, plus a little more to make up for any lost to disease, pests and other problems.
How much you want to harvest will dictate how many plants you need to grow and how much space you’ll need to grow them in. Some crops, such as tomatoes, produce many vegetables or fruits per plant, so you’ll need fewer of these plants to obtain a large harvest. Others such as carrots produce just one vegetable per plant and require correspondingly more to be sown. Here are our suggestions for some of the most common crops, remembering that yield will vary depending on your season length, soil, watering and the varieties you choose to grow:
Potatoes
- Harvest per person required: 75-200lbs (34-91kg) per person
- Yield per 10 foot (3m) row: 10-20lbs (4.5-9kg)
- Row length needed: 75-100 feet (23-30m), which is about 85 plants
Carrots
- Harvest per person required: 7-20lbs (3-9kg) should be suitable for one person
- Yield per 10 foot (3m) row: 7-10lbs (3-4.5kg)
- Row length needed: 10-20 feet (3-6m) which is about 30-60 plants
Tomatoes
- Harvest per person required: 15-65lbs (7-29kgs) per person
- Yield per 10 foot (3m) row: 15-45lbs (7-20kg)
- Row length needed: 10-15 feet (3-5m), which is 6-10 plants
The Garden Planner makes it easy to work out the row length required for a certain number of plants, so for other crops just continue this process of working out how much you’ll eat, researching how much each plant yields, and how long the row will need to be.
How to get the most from your space
There are some tried and tested growing techniques which help you to get the most from any garden, no matter how big or how small.
Use different varieties.
Where possible, plant early, mid and late varieties of your crops. This will provide a steady flow of produce spread throughout the season, and can also help to reduce losses due to pests and diseases as your plants will be in different stages of growth at different times.
For example, if you’re growing potatoes you could choose 3 different varieties –one each of first early, second early and maincrop varieties. Many other crops have seasonal varieties too, including peas, beans, apples, onions and sweetcorn.
Succession plant
Succession planting is all about maximising the space you have available, ensuring that there is always something growing in the ground. As you harvest your first early potatoes in June, you could then plant a quick growing crop such as some beetroot. The Garden Planner can help to keep track of this – set the dates that crops will be in the ground and select a specific month to see what space will be available, then pop in a few rows of your chosen succession crop.
Extend your season and protect your crops.
Use greenhouses, cold frames or a hoop house to add an extra few weeks at the start and end of the growing season. In cooler climates this will ensure you are much more successful with tender crops like tomatoes, cucumbers and melons. They will also help to protect your crops from unseasonal weather such as wet summers and from some pests such as birds, small mammals and deer. Plus, it’s always welcome to be able to harvest fresh produce early in the season.
Grow calorie crops
Calorie crops are those which have a high calorie content per weight of crop. If you’re growing lots of your own food, you’ll want to include the top 5 of potatoes, sweetcorn, beans, winter squash and perhaps grains such as wheat. These crops fill you up, are generally much less work than other crops and are very versatile – they store well, for long periods and are endlessly useful in the kitchen.
Growing any fresh food in your garden is a great way to feed your family – it doesn’t have to be about being totally self-sufficient. Whether you have a few containers by your back door or have a 2 acre plot you’ll be able to add fresh ingredients to your meals and reduce your grocery bills, and if you garden organically and sustainably you’ll be reducing your environmental impact too.