Sweet Potato
Ipomoea batatas
Sweet potatoes are increasingly popular for warmer regions, with modern UK-adapted varieties like 'Beauregard' and 'Murasaki' giving reliable crops outdoors in the south or under cover further north. They're grown from rooted cuttings called slips, planted out in early June after all frost risk has passed. Slips need warm soil (above 15°C) — fleece or a polytunnel speeds them up. Train trailing vines along the ground or up netting; pinch out tips to encourage tuber formation. Harvest carefully in October before the first frost, when leaves yellow. Cure tubers in a warm, humid place for 7–10 days after lifting — this develops sweetness and toughens the skin for storage. Properly cured sweet potatoes keep for 4–6 months.
Plan where to grow Sweet Potato using our vegetable garden planner.
When to Sow Sweet Potato
Sow sweet potato in May, June.
Time to Harvest Sweet Potato
Expect to harvest approximately 4 months after sowing.
Companion Plants
Expected Yield
Expect 0.5–1.5kg of tubers per plant under good conditions.
Common Problems with Sweet Potato
Poor tuber formation
Caused by cool soil or excessive nitrogen. Plant into warmed soil (use black plastic mulch to raise temperature) and avoid high-nitrogen feeds. Vines should be lush but not overwhelmingly leafy.
Tubers rotting in storage
Untreated tubers rot quickly. Cure for 7–10 days at 25–30°C and high humidity after lifting — this heals nicks and toughens skin. Store at 12–15°C in a frost-free shed or cupboard.
Slug damage to tubers
Slugs hollow out tubers underground. Use nematode controls in summer and lift at the first sign of slug holes. Growing in raised beds or large containers reduces risk.
Plan your sweet potato in the allotment planner
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Cherry Tomato
Solanum lycopersicum var. cerasiforme
Cherry tomatoes are one of the most rewarding crops for UK allotment growers. These small, sweet fruits ripen reliably even in cooler summers, producing heavy trusses from July right through to October. They thrive in grow bags, pots, or directly in the ground, making them versatile for any plot size. Pinch out side shoots regularly on cordon varieties to channel energy into fruit production. Bush varieties like 'Tumbling Tom' need no training and work brilliantly in hanging baskets. Feed weekly with a high-potash tomato feed once the first fruits set. The key to great flavour is letting them ripen fully on the vine rather than picking early.
Beefsteak Tomato
Solanum lycopersicum
Beefsteak tomatoes produce the large, meaty fruits that are perfect for slicing into sandwiches and burgers. They need a long growing season in the UK, so starting seeds early under cover is essential. These are almost always grown as cordons — train them up a single stem, removing side shoots weekly. Each truss produces fewer but much larger fruits than cherry types, often weighing 200–500g each. They benefit from greenhouse growing in cooler regions, though sheltered outdoor spots in the south can produce good results. Consistent watering is critical; irregular watering causes blossom end rot and fruit splitting. Stop the plant at 4–5 trusses to ensure fruits ripen before autumn.
Nantes Carrot
Daucus carota
Nantes carrots are the gold standard for flavour — sweet, crisp, and cylindrical with a smooth skin that barely needs peeling. They perform well in most UK soils but prefer light, stone-free ground to grow straight. If your soil is heavy clay, grow them in raised beds or deep containers filled with sandy compost. Sow thinly to avoid the need for heavy thinning, which attracts carrot fly. Cover rows with fine mesh or enviromesh as a physical barrier against carrot fly — this is far more reliable than companion planting alone. Successional sowing from March to July gives you carrots from June through to winter. Late sowings can be left in the ground over winter under a thick mulch of straw.
Butterhead Lettuce
Lactuca sativa
Butterhead lettuce produces soft, rounded heads with tender, buttery-textured leaves that melt in the mouth. It's one of the quickest salad crops to grow — ready in as little as 8 weeks from sowing. Unlike iceberg types, butterheads tolerate partial shade and are less likely to bolt in warm spells. Sow small batches every 2–3 weeks from March to September for a continuous supply. They work well as an intercrop between slower-growing vegetables like brassicas and leeks. Water consistently but avoid wetting the leaves to reduce the risk of grey mould. 'All the Year Round' is the classic UK variety and lives up to its name, performing well in almost every season.