Jalapeño
Capsicum annuum 'Jalapeño'
Jalapeños are the world's most popular medium-heat chilli — thick-walled, juicy, and with a clean fruity heat (2,500–8,000 SHU) that's perfect for nachos, salsa, and pickling. They're well-suited to greenhouse or polytunnel growing, with a sheltered sun-trap working in southern gardens. Sow seeds in February or March on a heated propagator. Pot on into 2-litre pots and grow on under cover. Pinch out the growing tip at 30cm for bushy growth and stake plants — laden branches snap easily. Pick fruits green for maximum heat, or leave to ripen red for a sweeter, smokier flavour (perfect for chipotle if smoked). Feed weekly with tomato food once flowers appear. Each plant produces 25–50 fruits over the season.
Plan where to grow Jalapeño using our vegetable garden planner.
When to Sow Jalapeño
Sow jalapeño in February, March.
Time to Harvest Jalapeño
Expect to harvest approximately 5 months after sowing.
Companion Plants
Expected Yield
Each plant produces 25–50 fruits — a single plant gives a year's supply for most cooks.
Common Problems with Jalapeño
Flower drop without setting fruit
Caused by temperatures above 32°C, dry air, or lack of pollinators. Ventilate the greenhouse on hot days, mist plants in the morning, and tap flowers gently to aid pollination.
Branches snapping under fruit weight
Laden branches break easily. Stake each plant and tie in main stems; consider individual fruit trusses if the plant is heavily loaded.
Cracking or 'corking' on fruit skin
Light tan lines along the fruit shoulders are normal for jalapeños and indicate full maturity — not a problem. Fruits eat just as well.
Related guides
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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.