Essential in the Americas’ diet, especially in Mexico and the Andean region, sweetcorn is delicious even when just boiled with a bit of salt and butter.

Sweetcorn grows easily in long hot summers, but new selections suit better UK’s cool climate. Sow indoors at 18-21°C from mid-April to early May in modules of 2.5cm. To have an extended cropping season, try sowing another two times, 3 weeks apart. Cultivate it earlier in colder regions. To sow outdoors, the best moment is late spring. Sow 2 or 3 seeds per station and leave 45cm between stations.

Soil temperatures should be at least 10°C. Sweetcorn grows better in sunny, but sheltered positions, protected from strong wind. The soil should be fertile, so you can add up to two bucketfuls of organic matter/rotted manure and about 100g per sq m of general purpose fertiliser before planting. 

Check the ripeness when the tassels become brown by peeling a bit of the husk and piercing the kernel with a fingernail. If a watery liquid squirts out, it’s unripe. If it’s creamy, it’s ready. If it’s paste-like, it’s over-mature. 
To harvest, twist ripe cobs and pull them from the stem. For a better taste, harvest when required to use.

Top Tips

– Don’t grow different cultivars next to each other as cross pollination might lead to poor flavour.

– Sweetcorn is pollinated by the wind, so it’s better to grow it in blocks instead of rows; keeping the blocks 45cm apart.

– Stake the plants individually if they get tall or if the location is exposed.

– Tap the top of the plants when the male flowers open to help pollination of the female flowers below them.

Key timings

Jan Feb March April May June July Aug Sep Oct Nov Dec


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