When to plant sweet corn by zone
Zea mays is a warm-season crop that is tender to frost. Rule of thumb: direct sow from 1 week after to 5 weeks after the last frost.
Sweet Corn planting dates by zone
Each row uses the median 30%-risk frost dates of the major cities in that zone; rows marked * have no major city and use the median of NOAA stations in that zone instead. Frost dates vary a lot within a zone, so use your city page for local dates. In frost-free climates: Feb 15 – Apr 15; Aug 1 – Aug 31.
| Zone | Median last frost | Start indoors | Transplant / plant out | Direct sow | Fall crop |
|---|---|---|---|---|---|
| 1a* | May 29 | — | — | Jun 5 – Jul 3 | — |
| 1b* | May 29 | — | — | Jun 5 – Jul 3 | — |
| 2a | May 21 | — | — | May 28 – Jun 25 | — |
| 2b* | May 20 | — | — | May 27 – Jun 24 | — |
| 3a* | Jun 4 | — | — | Jun 11 – Jul 9 | — |
| 3b* | May 24 | — | — | May 31 – Jun 28 | — |
| 4a | May 12 | — | — | May 19 – Jun 16 | — |
| 4b | May 5 | — | — | May 12 – Jun 9 | — |
| 5a | May 4 | — | — | May 11 – Jun 8 | — |
| 5b | May 4 | — | — | May 11 – Jun 8 | — |
| 6a | May 4 | — | — | May 11 – Jun 8 | — |
| 6b | Apr 26 | — | — | May 3 – May 31 | — |
| 7a | Apr 22 | — | — | Apr 29 – May 27 | — |
| 7b | Apr 10 | — | — | Apr 17 – May 15 | — |
| 8a | Apr 1 | — | — | Apr 8 – May 6 | — |
| 8b | Mar 22 | — | — | Mar 29 – Apr 26 | — |
| 9a | Mar 11 | — | — | Mar 18 – Apr 15 | — |
| 9b | Feb 12 | — | — | Feb 19 – Mar 19 | — |
| 10a | Jan 26 | — | — | Feb 2 – Mar 2 | — |
| 10b | Jan 27 | — | — | Feb 3 – Mar 3 | — |
| 11a | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| 11b* | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| 12a* | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| 12b | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| 13a* | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| 13b* | Rare | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
Growing tips
- Plant in blocks, not single rows, for good wind pollination.
- Supersweet (sh2) types need warmer soil (65°F+) than standard types.
- Stagger sowings two weeks apart to extend the harvest.
Related guides: which frost date to use · succession and fall planting.
Exact dates for your city
Popular: New York, Los Angeles, Chicago, Houston, Phoenix, Philadelphia, San Antonio, San Diego, Dallas, Jacksonville, Fort Worth, San Jose — or browse all cities by state.
Other crops: Tomato, Pepper, Lettuce, Green Beans, Zucchini & Summer Squash, Cucumber, Carrot, Onion, Potato, Basil, Spinach, Kale, Broccoli, Peas, Eggplant, Cabbage, Radish, Strawberry, Beets
Sweet Corn planting questions
When can I plant sweet corn outside?
Sow seed directly from 1 week after to 5 weeks after the last frost, once the soil reaches about 60°F (15.6°C). Examples: zone 5a (median last frost May 4): May 11 – Jun 8; zone 6b (median last frost Apr 26): May 3 – May 31; zone 8a (median last frost Apr 1): Apr 8 – May 6.
Is my growing season long enough for sweet corn?
Sweet corn needs 65–90 days from sowing, and must finish before fall frost. Counting from planting 1 week after the last frost plus two weeks of harvest, slower varieties need about 111 days between the 30% frost dates. That is longer than the season in 3 of the 460 cities on this site with frost dates — for example Bend, OR, Flagstaff, AZ, Fairbanks, AK — where early varieties are the safer choice.
What soil temperature does sweet corn need?
At least 60°F (15.6°C) at planting depth. Cold soil slows germination more than a short delay in planting does, so in a cold spring it pays to wait a week past the usual date. As a tender crop, sweet corn cannot take frost.
How far apart should I plant sweet corn?
Recommended in-row spacing: 8–12 in, blocks of 4+ rows. Plant in blocks, not single rows, for good wind pollination.
When do you plant sweet corn where frost is rare?
In frost-free climates, plant sweet corn Feb 15 – Apr 15 and Aug 1 – Aug 31, timing growth for the mildest months. This applies to cities such as Los Angeles, CA, San Diego, CA, San Francisco, CA.