When to Plant Sweet Corn
Sweet corn is a tender warm-season vegetable. Frost damages it, so it goes out only after the last spring frost.
Sow it outdoors from the last spring frost to 3 weeks after it. The first harvest comes about 65 to 90 days after sowing.
Example dates
The same rules in dates for three climates, using typical frost dates. Enter your ZIP code above for the dates where you live.
| Task | Last frost Mar 15first Nov 15 | Last frost Apr 15first Oct 25 | Last frost May 15first Sep 30 |
|---|---|---|---|
| Sow outdoors | Mar 15 – Apr 5 | Apr 15 – May 6 | May 15 – Jun 5 |
| Harvest | May 19 – Jun 2 | Jun 19 – Jul 3 | Jul 19 – Aug 2 |
Growing sweet corn
Plant in a block of at least four short rows rather than one long row so the ears pollinate fully.
- Spacing: 10 in apart, in rows 30 in apart. In a raised bed, 1 per sq ft at square-foot spacing.
- Days to harvest: 65 to 90 from sowing, then about 2 weeks of picking.
- Successions: sow again every 14 days for a steady supply. See succession planting.
- Rotation: plant it in a different bed each year. See crop rotation.
- Traditional companions: bush bean, cucumber, head lettuce, leaf lettuce, parsley, pea (shelling/snap/snow), pole bean, potato, pumpkin, romaine lettuce, sage, summer squash (zucchini/yellow), sunflower, winter squash. See companion plants for sweet corn.
- Usually kept apart from: cherry tomato, tomato.
Plan your beds with these dates
Draw your beds, tap squares to plant sweet corn and everything else, and get every crop's dates for your ZIP code in one calendar. Free, in your browser.
Open the garden plannerQuestions
Can sweet corn go in before the last frost?
No. Sweet corn is damaged by frost: sow it from the last spring frost to 3 weeks after it.
How long does sweet corn take to grow?
About 65 to 90 days from sowing to the first harvest, which then lasts about 2 weeks. Varieties differ: check the seed packet.
How often should I sow sweet corn?
Every 14 days or so for a steady harvest, until the last sowing that still ripens before your first fall frost. The planner works that date out for your ZIP code.
More planting dates
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020 (annual/seasonal, by station: freeze dates at 32 °F)
- Colorado State University Extension: Vegetable Planting Guide (CMG GardenNotes #720)
- Virginia Cooperative Extension, Virginia Tech: Virginia's Home Garden Vegetable Planting Guide: Recommended Planting Dates and Amounts to Plant (426-331 / SPES-673P, 2025)
- University of Maryland Extension: Vegetable Planting Calendar for central Maryland
- UNH Cooperative Extension: Growing Vegetables: When to Plant your Vegetable Garden (2016)
- NC State Extension: Extension Gardener Handbook, Chapter 16: Vegetable Gardening
- WSU Extension: Pacific Northwest Gardener's Handbook, Chapter 7: Vegetable Gardening
- Iowa State University Extension and Outreach: Vegetable Planting and Harvesting Times (chart, central Iowa)
- Iowa State: Growing Sweet Corn in the Home Garden
- Utah State University Extension: Suggested Vegetable Planting Dates for Utah
- UC Master Gardener Program, UC ANR: Companion Planting Chart: Companion Planting for Edible Crops
- University of Wisconsin–Madison Extension, Kenosha County: Companion Plants for the Vegetable Garden (column, 2012)
- Oregon State University Extension Service: Companion Planting (Food Hero, 2021)
- Oregon State University Extension Service: Herbs and Flowers in the Vegetable Garden
- Utah State University Extension, Utah 4-H: Creating Sustainable School and Home Gardens: Companion Planting (2025)
- University of Arizona Cooperative Extension, Yavapai County: The Art of Companion Planting (Master Gardener presentation, 2023)
- Clemson Cooperative Extension HGIC: Plant Partners: 5 Benefits of Companion Planting (2025)
- N.C. A&T State University Cooperative Extension: Five Veggies You Can Grow at Home
- UF/IFAS Florida-Friendly Landscaping Program: Companion Planting (FFL in a Minute, 2020)