Growing Tomatoes in Pots on a Patio

Why tomatoes thrive in patio pots

UK gardeners often fight grey skies and cool nights, but tomatoes are surprisingly adaptable when given a warm, sheltered spot. A south- or west-facing patio wall traps heat, and pots let you chase the sun as the season shifts. The secret is choosing compact varieties. Bush types such as 'Tumbling Tom', 'Maskotka' and 'Lizzano' stay neat and need no pruning. Cordon varieties like 'Gardeners' Delight', 'Sungold' or 'Mountain Magic' crop heavily if trained up a cane. Avoid huge beefsteak types; they demand more root room than a pot can offer. Even a small patio can produce a steady supply if you give plants consistent care from June onwards.

Choosing pots, compost and a potting shed base

Size is everything. A bush tomato needs at least 10 litres of compost; a cordon wants 20–30 litres. A 30 cm diameter pot is a sensible minimum. Terracotta dries out fast, so glazed ceramic or thick plastic holds moisture better. Drainage holes are non-negotiable — tomatoes loathe waterlogged roots. Fill with peat-free multipurpose compost mixed with a handful of perlite or horticultural grit. If you have a potting shed, use it to mix compost, store canes and raise seedlings early. An allotment retreat works too: a quiet corner for potting on and a water butt for soft rainwater.

• Bush tomatoes: 10–15 litres, 25–30 cm pot.
• Cordon tomatoes: 20–30 litres, 30–40 cm pot.
• Cherry types: can manage in 10 litres if fed well.

Planting, supporting and early care

Wait until late May or early June, after the last frost, to move plants outside. Harden them off over a week by putting them out during the day and bringing them in at night. Plant deeply — bury the stem up to the first pair of leaves — and water well. For cordons, push a sturdy cane into the pot and tie the stem loosely as it grows. Remove sideshoots that appear between the leaf and the main stem. Bush types need no pruning. A mulch of compost or gravel keeps moisture in and stops soil splashing onto leaves. Pinch out the growing tip of cordons once four or five trusses have set, so energy goes into ripening fruit rather than more foliage.

Watering for steady, unblemished fruit

Irregular watering causes blossom end rot — that black, sunken patch on the fruit. Aim for consistently moist compost, never soggy. In hot weather, you may need to water twice daily. A self-watering pot or a simple drip system helps if you're away. Water in the morning, at the base, avoiding the leaves. A potting shed is a handy place to store a full watering can so it's ready when you are. Group pots together to create a humid microclimate, which helps flowers set fruit even in breezy weather. A layer of gravel on the compost surface reduces evaporation and keeps slugs at bay.

Feeding for flavour and yield

Once the first flowers set fruit, start feeding weekly with a high-potash tomato fertiliser. Dilute according to the packet — usually one capful per 5 litres. Don't feed before fruit sets, or you'll get lush leaves and few tomatoes. For cordons, pinch out the growing tip after four or five trusses have formed, so energy goes into ripening. Keep picking ripe fruit to encourage more. A comfrey or seaweed feed works well for organic growers. If you're on an allotment retreat, share the harvest — nothing beats a warm, sun-ripened tomato straight from the vine.

Troubleshooting and small-space wins

Greenfly and whitefly can be blasted off with water or a soap spray. Blight strikes in wet summers; remove affected leaves promptly and grow blight-resistant varieties like 'Crimson Crush' or 'Mountain Magic'. Green tomatoes at season's end? Ripen them on a sunny windowsill with a banana, or make chutney. Even a tiny patio can yield a steady supply. Use a potting shed or corner of an allotment as a retreat for storing tools, potting on seedlings and escaping the weeds. With consistent care, you'll be picking ripe tomatoes from July until the first frosts.

• Blossom end rot: water consistently, add a little lime to compost.
• Greenfly: spray with soapy water or encourage ladybirds.
• Blight: remove affected leaves, grow resistant varieties.
• Split fruit: caused by irregular watering; mulch and water steadily.