Celeriac
Apium graveolens var. rapaceum
Celeriac is an underrated vegetable that deserves a place on every UK allotment. This knobbly, celery-flavoured root produces a large, dense bulb above the soil surface that's superb roasted, mashed, made into soup, or grated raw in a classic remoulade. It's easier and more reliable to grow than celery in UK conditions, as it's less prone to bolting and doesn't need blanching. Start seeds early — sow on the surface of moist compost in February or March, as the tiny seeds need light to germinate, at 15–20°C. Germination is slow and erratic (2–3 weeks). Prick out seedlings into modules and grow on in a cool greenhouse or cold frame. Plant out in late May, 30cm apart, into rich, moisture-retentive soil that's been heavily enriched with well-rotted compost. Keep consistently watered throughout summer — celeriac has shallow roots and dislikes drought. Remove lower leaves from July onwards to expose the developing bulb to light. Harvest from October to March — celeriac is fully frost-hardy and can be left in the ground over winter with a protective mulch of straw. 'Monarch' and 'Prinz' are reliable UK varieties. The leaves can be used as a celery substitute in stocks and soups.
Plan where to grow Celeriac using our vegetable garden planner.
When to Sow Celeriac
Sow celeriac in February, March.
Time to Harvest Celeriac
Expect to harvest approximately 8 months after sowing.
Expected Yield
One bulb per plant (500g–1kg when mature). Harvest October to March; stands frost in the ground.
Growing Tips
Surface-sow; needs light to germinate. Remove lower leaves from July.
Common Problems with Celeriac
Small, undersized bulbs
Usually caused by late sowing, drought, poor soil, or too much competition from weeds. Sow early (February–March) to give the long growing season celeriac needs. Enrich soil generously with compost, water consistently, and keep weed-free. Remove lower leaves from July to direct energy into the bulb.
Celery leaf miner
Larvae tunnel within the leaves, creating white or brown blister-like mines. Pinch affected leaves to crush the larvae inside, or remove and destroy mined leaves. Cover plants with fine enviromesh to prevent egg-laying flies. Damage is usually cosmetic and doesn't affect the root crop severely.
Slugs hollowing out the bulb
As the bulb swells at ground level, slugs can burrow into the flesh, creating holes that allow rot to enter. Use organic slug pellets or nematode biological control. Remove lower leaves and any debris around the plant to eliminate hiding places. Harvest promptly if slugs become a serious problem.
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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.