Now is a good time to sow Sweetcorn. Follow the sowing guide below.
Growing Calendar
This month: May
Log to journalStart seeds indoors this week
- •Fill tray with compost
- •Sow seeds evenly
- •Cover lightly with soil
- •Water gently
- •Place in warm light spot
Watch Out For
Cold soil below 10°C causes poor germination and sluggish growth
do not plant out until the soil has warmed; even a June planting will still crop in time
Mice steal freshly sown seeds
protect outdoor sowings with fleece or a cloche until seedlings are well established
Sweetcorn needs consistent watering once cobs begin to swell
irregular moisture at this stage causes gapped cobs with missing kernels
Grown Organically
Every method in this guide works with natural systems — no synthetic chemicals, no shortcuts.
Read our approachCommon Questions
About growing Sweetcorn in the UK
Why must I plant sweetcorn in a block?
Sweetcorn is wind-pollinated — pollen falls from the male tassels at the top onto the female silks below. In a single row, most pollen blows away and few cobs are pollinated. A block of at least 4×4 plants ensures the pollen clouds stay within the planting area.
When is sweetcorn ready to harvest?
Harvest sweetcorn when the silks at the top of the cob have turned dark brown, and the cobs feel plump and full. Test by peeling back a small section of husk and pressing a kernel — the juice should be milky, not clear or starchy. Eat as soon as possible after harvesting.
Can I grow sweetcorn in the UK?
Yes — modern varieties bred for UK conditions reliably produce cobs in a good summer. Choose early varieties (Swift, Earlibird, Lark) and start under glass to give the longest possible season. Sweetcorn needs a sunny, sheltered position to succeed.
Why are my sweetcorn cobs small or empty?
Poor pollination is the most common cause of small or incomplete cobs. This happens when plants are grown in rows rather than blocks, or when weather is very wet and windy during pollination. Shaking the plants gently when tassels are producing pollen can help in poor conditions.
Member guides
There's more to growing Sweetcorn than this guide covers.
Seasonal reminders, deeper guides, and the small adjustments that change a harvest.
