How to Grow Tomatoes: Container, Raised Bed and Garden Growing for a Bumper Crop

The flavour argument alone is compelling, but home-grown tomatoes offer advantages across several dimensions. Nutritionally, vine-ripened tomatoes contain significantly more lycopene (a carotenoid antioxidant with well-studied cardiovascular protective properties), vitamin C and beta-carotene than commercially harvested equivalents — a difference attributable entirely to the full ripening process. Economically, a single healthy indeterminate tomato plant can produce 4–8 kg of fruit from a £3–5 plant, with seeds being even more economical at under £3 for dozens of plants. Environmentally, home growing eliminates the refrigerated transport chain and excessive packaging that characterises supermarket tomatoes. Varieties available to the home grower also dwarf what is commercially available — over 10,000 named tomato varieties exist, while supermarkets typically stock 5–10. The 'Costoluto Fiorentino' (an Italian ribbed heirloom), 'Sungold' (an extraordinarily sweet orange cherry), 'Black Krim' (a dark, complex-flavoured beefsteak) and 'Green Zebra' (tart, striped, visually striking) represent a world of flavour experience entirely inaccessible without growing your own.

Tomato varieties divide into two growth types. Determinate (bush) varieties grow to a fixed height (typically 60–120 cm), set all their fruit within a concentrated period, then stop growing — ideal for containers, small spaces and those who want a concentrated harvest for preserving. Key varieties: 'Tumbling Tom' (compact, excellent for hanging baskets), 'Maskotka' (trailing, prolific), 'Roma' (determinate, ideal for sauce). Indeterminate (cordon or vining) varieties continue growing throughout the season until frost kills them, potentially reaching 2–3 m, producing fruit continuously over a long period — better for ongoing fresh eating. Key varieties: 'Sungold F1', 'Gardener's Delight', 'Costoluto Fiorentino', 'Black Krim', 'San Marzano'.

For containers, choose pots of at least 30–40 litres capacity — tomatoes have extensive root systems and suffer significantly in undersized pots, producing less fruit and being prone to nutrient and water stress. Use a high-quality peat-free compost mixed with 20–30% perlite for drainage and aeration. For raised beds, build to at least 30 cm depth and fill with a blend of good topsoil, compost and well-rotted manure. In open ground, improve clay soils with grit and organic matter; improve sandy soils with substantial organic matter to increase water retention. All tomatoes require full sun — a minimum of 6–8 hours of direct sunlight per day.

In the UK, sow tomato seeds indoors from late February to early April. Use individual small pots or module trays filled with seed compost, sowing seeds approximately 5 mm deep, covering lightly and placing on a heated propagator at 18–22°C. Germination typically takes 7–14 days. Once seedlings show their first true leaves (the second set after the initial seed leaves), pot up into 9 cm pots filled with general potting compost. Maintain warmth and good light — insufficient light at this stage produces leggy, weak seedlings. Do not plant outdoors until all risk of frost has passed, typically late May to early June in most of the UK, varying by region. Harden off plants for 7–10 days before transplanting: place outdoors in a sheltered spot during the day and bring in at night, gradually increasing outdoor exposure.

When transplanting, plant deeply — up to the lowest set of leaves — as tomatoes produce adventitious roots from buried stem sections, resulting in a stronger, better-anchored root system. Space cordon varieties 45–60 cm apart in rows 75–90 cm apart; bush varieties according to their mature spread. Install strong supports immediately for cordon varieties — bamboo canes, tomato cages or string systems — before the plant needs them.

Tomatoes are heavy feeders with specific nutritional requirements that change across their growth cycle. During the vegetative phase (before flowers appear), they need nitrogen-rich feeding to support leaf and stem development. Once the first flowers appear, switch to a high-potassium tomato fertiliser — look for NPK ratios with elevated potassium (K), such as 4-4-8 or similar. Potassium is essential for fruit development, sugar accumulation and disease resistance. Commercial tomato feeds (Tomorite, Miracle-Gro Tomato) are formulated for this later stage. Feed every 7–14 days once flowering begins, following pack instructions.

For cordon varieties, sideshooting is essential — remove the small shoots that develop in the angle between the main stem and each leaf stem (the axillary shoots). If left, these develop into new stems, diverting energy from fruit production and creating an unmanageable plant. Pinch out between finger and thumb or use clean scissors. Remove sideshoots when small (under 5 cm). Allow 4–6 trusses (flower clusters) to develop, then pinch out the growing tip to direct all remaining energy into ripening existing fruit. Water consistently and deeply rather than little and often — irregular watering causes blossom end rot (calcium uptake failure due to water stress) and fruit splitting.

Blossom end rot produces dark, sunken patches on the base of developing fruit. It is caused not by calcium deficiency in the soil but by calcium uptake failure due to inconsistent watering — irregular soil moisture prevents calcium from moving through the plant. The fix is consistent, deep watering and a regular mulch to maintain moisture levels. Blossom drop (flowers falling before setting fruit) most commonly results from temperature extremes — temperatures below 10°C or above 32°C prevent pollen release. Improving ventilation in a greenhouse and avoiding excessive nitrogenous feeding (which promotes leafy growth over flowering) usually resolves it.

Late blight (Phytophthora infestans) is the most serious tomato disease in wet climates, producing dark patches on leaves that spread rapidly in humid conditions. There is no cure once established — prevention through good airflow, avoiding overhead watering, and removing affected material promptly are essential. Blight-resistant varieties including 'Crimson Crush', 'Ferline' and 'Fantasio F1' are strongly recommended for UK growers in wetter regions. Aphids cluster on growing tips and the undersides of leaves — blast off with water or use organic neem oil spray. Encourage ladybirds and lacewings by planting companion flowers such as marigolds and calendula nearby.

Tomatoes are ready to harvest when they reach full colour development for their variety and yield slightly to gentle pressure. For most red varieties, this means full red colouration and a slight give — not hard, not squashy. 'Sungold' should be deep orange rather than pale yellow. 'Black Krim' is ready when deep burgundy-brown on the shoulders. Taste is always the final arbiter. Harvest regularly — leaving ripe tomatoes on the plant reduces the plant's incentive to continue producing. At the end of the season, before frost threatens, harvest all mature green tomatoes and ripen indoors at room temperature (not the fridge — cold destroys flavour enzymes). Place in a single layer with good airflow and check daily.

Store ripe tomatoes at room temperature, never in the fridge — refrigeration below 12°C halts the enzymatic processes that develop flavour and causes cell damage that makes texture mealy. Use within 3–5 days of full ripeness. For preserving: slow-roast excess tomatoes at 140°C for 2–3 hours with olive oil, salt and thyme to produce intensely flavoured, concentrated tomatoes that freeze beautifully. Make passata or tomato sauce in batches and freeze in portions. Dehydrate sliced tomatoes in a food dehydrator or low oven for 6–8 hours to produce your own sun-dried tomatoes.

In the UK and northern climates, the outdoor tomato season is short — typically July to October for the main harvest. Several strategies extend it meaningfully. Starting plants early under heat (late February) and moving them to an unheated polytunnel or greenhouse in April rather than outdoors in May gives 6–8 additional weeks of warm growing conditions. At the end of the season, placing fleece or cloches over outdoor plants can buy another 2–4 weeks before hard frosts arrive.

Under glass, growing conditions are available year-round in theory, though supplementary lighting is required for winter growing in northern latitudes where daylight hours are insufficient. Cherry tomato varieties such as 'Hundreds and Thousands' and 'Tumbling Tom' can be grown indoors on a south-facing windowsill during winter with supplementary LED grow lighting. Succession planting — starting a second batch of fast-maturing cherry tomatoes in June — can extend outdoor harvest into November in mild years.

Saving seed from non-hybrid (open-pollinated or heirloom) varieties is both economical and increasingly rewarding as saved seed adapts over generations to local conditions. Ferment seeds in their gel coating with water for 3 days to remove germination inhibitors, rinse, dry on paper and store in a cool, dry, dark location.