Vegetable growing depends on sun, soil improved with organic matter, and sowing dates set by the last frost, which varies by several weeks between the south and the north.
Salads, beans, courgettes, beetroot and early potatoes are reliable first crops, and many vegetables grow well in containers.
A vegetable plot does not need to be large. A few raised beds, a strip of border or a group of containers produces worthwhile crops, and the principles are the same at any scale: light, decent soil, water and sowing at the right time.
Most vegetables need at least six hours of direct sun a day in summer. Leafy crops such as lettuce, spinach, chard and rocket tolerate partial shade; fruiting crops such as tomatoes, courgettes and beans do not. Shelter from wind matters almost as much as sun, particularly for climbing beans and sweetcorn.
Soil is improved by adding organic matter such as garden compost or well-rotted manure, either dug in or spread on the surface as a mulch for worms to draw down. The second approach, known as no-dig, disturbs fewer weed seeds and has become widespread on allotments. Raised beds filled with a mix of topsoil and compost suit sites with poor drainage or very stony ground, and beds no wider than about 1.2 metres can be worked from the paths without treading on the soil.
The growing season is set by frost. In much of southern England and the milder parts of western Europe the last frost usually falls in late April or early May; in northern England, Scotland and at altitude it can be late May or June. Seed packets give sowing windows, but local conditions decide the date.
Young plants raised indoors need a week or two of hardening off, standing outside by day and returning under cover at night, before they are planted out.
Some crops forgive mistakes better than others. Salad leaves, radishes, courgettes, chard, beetroot, runner and French beans, early potatoes and garlic are reliable in most gardens. Cauliflower, celery and aubergines are more demanding, and outdoor tomatoes are a gamble in a wet summer because of blight.
Fast crops such as lettuce, radish and rocket are sown in short rows every two or three weeks so that they do not all mature together. Courgettes are the classic example of over-planting: two plants are usually enough for a household.
Growing the same family of vegetables in the same ground year after year lets soil-borne pests and diseases build up, notably clubroot in the cabbage family and white rot in onions. Rotation moves each group to a new bed annually. A common scheme uses four groups: potatoes and tomatoes; peas and beans; cabbages and other brassicas; and roots and onions. Perennial crops such as asparagus, rhubarb and soft fruit stay outside the rotation.
A thorough soak once or twice a week encourages deeper roots than a daily sprinkle. Water is most needed when seeds are germinating, when transplants are settling in, and when pods, fruits and tubers are swelling. A mulch of compost holds moisture in the soil and suppresses weeds.
Soil given compost every year needs little extra fertiliser for most crops. Hungry plants in containers, especially tomatoes, are fed weekly with a high-potash liquid feed once the first fruits have set.
Slugs and snails do most damage to seedlings and young transplants. Fine insect mesh keeps carrot fly off carrots, and cabbage white butterflies and pigeons off brassicas. Potato and tomato blight, a disease that spreads in warm, humid weather from midsummer, is avoided by growing early potatoes, choosing resistant varieties and keeping tomatoes under cover.
Salads, herbs, chillies, dwarf beans, tomatoes, potatoes and courgettes all crop in pots or growing bags on a patio or balcony. Bigger containers hold more water and are easier to manage; a pot of 30 to 40 litres suits one tomato or courgette plant. Peat-free compost is used fresh each year for hungry crops, and the spent compost can be spread on beds as a mulch.
Households without a garden can rent an allotment. In England and Wales, outside inner London, local councils have a legal duty to provide allotments where there is demand, and many sites are run by parish councils or allotment associations. Waiting lists are long in most towns, and some sites offer half or quarter plots to shorten them. Community gardens and shared growing schemes are an alternative where plots are scarce.