Field guide
How to grow sweet corn: planting, care, and harvest guide
Sweet Corn typically reaches first harvest in 60–100 days. This guide covers when to plant by USDA zone, common pests, harvest cues, and companion plants where relevant.
Open plannerWhen to plant sweet corn by USDA zone group
- USDA Zones 1–4 — June
- USDA Zones 5–6 — May to June
- USDA Zones 7–8 — April to May
- USDA Zones 9–10 — March to April
- USDA Zones 11–13 — February to April
Companion plants
Good companions: beans, Winter Squash, Cucumbers, Peas
Avoid planting with: Tomato (Slicing)
Harvest
When to pick
- Silks turn dark brown and dry
- Ears feel full and plump when squeezed through the husk
- Puncture a kernel — milky liquid means ready; clear means wait; pasty means past prime
How: Grab the ear firmly and snap downward while twisting. Cook immediately — sugar starts converting to starch the moment it's picked.
Storage: Best eaten same day. Refrigerate husked ears in a wet towel for 1-2 days max. Blanch and freeze for longer storage.
Common pests and problems
Corn Earworm
Signs: Holes in husks, caterpillars and frass inside the ear tip
Control: Apply mineral oil or Bt to silk tips when they first appear. Plant early to avoid peak moth season. Remove and destroy affected ear tips at harvest.
Raccoons/Birds
Signs: Torn husks, partially eaten ears, stalks knocked down
Control: Electric fence (raccoons). Bird netting or paper bags over ears. Plant in blocks, not rows, for better pollination and easier protection.
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