vegetable
solanaceae family

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.

SunlightFull sun
WateringModerate
Height70cm
Spacing45cm
Germination10–21 days at 20–25°C
Sowing MethodUnder cover
Frost HardinessTender
Sowing Depth0.5cm

When to Sow Jalapeño

Sow jalapeño in February, March.

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Sowing months

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

Plan your jalapeño in the allotment planner

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