Tomatoes Growing Guide
Tomatoes are a highly popular crop that can be grown from seed indoors or bought as young plants, suitable for outdoor or greenhouse cultivation, in pots or in the ground. They are botanically known as Solanum lycopersicum and are available in a wide range of varieties differing in size, colour, texture, and flavour. Plant sizes also vary, from tall, vigorous cordon types to compact bush varieties and dwarf plants for containers, or trailing types for hanging baskets. They require regular watering and feeding, and protection from frost.
This guidance applies to the crop in general. Individual varieties and local conditions can differ.
Planting information
Sow seeds indoors from late February to mid-March for greenhouse growing, or late March to early April for outdoor cultivation. Seeds require a temperature of about 18°C (64°F) to germinate, ideally using a heated propagator or warm windowsill covered with a clear plastic bag to maintain humidity. Once seedlings appear (usually within two weeks), uncover them and provide maximum light to prevent legginess. After a couple of weeks, when seedlings have developed true leaves, prick them out and pot into individual pots or modules filled with peat-free multi-purpose compost. Replant leggy seedlings more deeply, so the first pair of leaves is just above the compost surface. Keep in a bright location at a minimum temperature of 16°C (60°F) and water regularly. They should be ready for final planting after about a month. Plant young, well-rooted tomato plants into their final position in early summer, once temperatures are reliably above 16°C (60°F). They can be planted in large containers, growing bags, or directly in the ground. For outdoor planting, choose a warm, sunny, sheltered location. Plant tomatoes deeply, so the first set of leaves is just above the soil surface, as the buried stem section will produce additional roots. Acclimatise plants to outdoor conditions by hardening off before planting out. For containers, plant one tomato plant in a 30–45cm (12–18in) pot or two in a standard growing bag. For planting in the ground, add plenty of garden compost for rich, free-draining but moisture-retentive soil. Space plants 45–60cm (18–24in) apart. For cordon types, insert a sturdy cane next to the plant and tie the main stem loosely. Avoid planting tomatoes in the same bed in consecutive years.
Harvesting information
Tomatoes start to ripen from mid-summer onwards, with timing varying by variety and conditions. Check plants every few days and pick fruits individually with the stalk attached, once they are ripe and fully coloured. At the end of the growing season, lift outdoor plants with unripe fruit and lay them on straw under cloches or pick the fruits and place them in a warm, dark spot to ripen. Alternatively, place unripe tomatoes in a drawer with a banana to aid ripening.