Tall annual grass producing edible immature ears. Wind-pollinated — plant in blocks, not rows, for proper pollination.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 2–11 | −45.6 °C to 10 °C | Zones where it can be grown as an annual — not a frost-tolerance rating |
| RHS hardiness rating | H1c | 5 °C to 10 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 2–9 | −40 °C and warmer | Zones where it can be grown as an annual — not a frost-tolerance rating |
| Australian (ANBG) zone | Zone 1–7 | −15 °C and warmer | Zones where it can be grown as an annual — not a frost-tolerance rating |
As a tender annual, Sweet corn doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.
About Sweet corn
Sweet corn is a mutant form of maize in which sugars are converted to starch more slowly, which is why it is eaten fresh and why older varieties lose sweetness within hours of picking. Maize itself is the most heavily transformed of all crop plants: its wild ancestor, teosinte, looks so unlike modern corn that the relationship was disputed for decades. It is wind-pollinated, which is why it is planted in blocks rather than single rows — each silk leads to a single kernel, and patchy cobs are a pollination failure rather than a nutrient problem.
Growing notes
- Soil temperature matters more than air — sow only when soil is consistently above 12 °C
- Plant in blocks of 4 × 4 minimum so wind can shake pollen from tassels onto silks
Categories
Related plants
Cross-check Sweet corn against your zones