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Vegetable
Sweet corn
Zea mays
A summer crop that needs warm soil, full sun and plenty of water. Plant in blocks of at least 4 by 4 rather than one long row, because corn is wind-pollinated and patchy pollination gives gappy cobs. Pick cobs when the silks turn brown and the kernels squirt milky juice.
- SunFull sun
- Spacing30 cm apart
- First pick11–14 weeks
- FrostFrost tender
- HeatHandles heat well
- Sow depth40 mm
When to plant where you live
Checking your area…
Add sweet corn to my gardenVarieties (3)
- Golden BantamHeirloom open-pollinated yellow corn; save your own seed
- Mini or early typesShorter plants and quicker cobs; good for small gardens
- Supersweet hybrids (e.g. Honey and Pearl)Very sweet and stays sweet after picking; keep away from other corn to avoid starchy cobs
Neighbours
Grows well with
From seed to plate
Plant
30 cm apart, rows 60 cm, seed 40 mm deep. Full sun.
Water
Plenty, especially at tasselling.
Feed
Compost and a nitrogen side-dressing.
Pick, from about 11 weeks
Ready when silks brown and kernels give milky juice.
Good to know
- Feed with a nitrogen-rich fertiliser when plants are knee high
- Eat or refrigerate as soon as possible after picking
- Grow climbing beans and pumpkins with it for a traditional three-sisters bed
Common problems
- Gappy cobsplant in a block and give plenty of water during tasselling
- Corn earworm (caterpillars in cob tips)cut out damaged tips; use a Bt-based registered product following label directions on silks if severe
- Plants blown overhill soil around stems and plant in a sheltered spot
- Seed rot in cold soilwait until soil is above about 16 °C
If you use a garden chemical, follow the label exactly. Try organic options first, and ask the community or Plant Doctor if you're unsure.
Guides
Where this information comes from
- Australian seed company regional sowing charts (temperate zone) (germination, low confidence)
- Alberta Agriculture: Soil temperature and field vegetable germination (FAQ) (germination, medium confidence, checked 27 Oct 2026)
- ABC Gardening Australia fact sheets (growing, medium confidence)
- Gardenate: Growing Sweet corn (comparison only) (growing comparison, medium confidence, checked 27 Oct 2026)
- Sustainable Gardening Australia: planting guides (sowing window, medium confidence)
Reviewed by AI cross-check (Claude), not a horticulturist on 27 Oct 2026. Version 2.