When to plant sweet potatoes
Sweet Potatoes are frost-tender: plant them out only after your last spring frost. Plant slips (rooted sprouts), not seeds, once the soil is thoroughly warm.
- Transplant outside 2–5 weeks after the last spring frost.
About 100 days from planting to harvest.
Get exact dates for your garden
Planting dates by hardiness zone
| Zone | Typical last frost | Start indoors | Transplant | Fall crop |
|---|---|---|---|---|
| 2a | May 24 | — | Jun 7 – Jun 28 | — |
| 3b | May 17 | — | May 31 – Jun 21 | — |
| 4a | May 12 | — | May 26 – Jun 16 | — |
| 4b | May 8 | — | May 22 – Jun 12 | — |
| 5a | May 3 | — | May 17 – Jun 7 | — |
| 5b | May 1 | — | May 15 – Jun 5 | — |
| 6a | Apr 29 | — | May 13 – Jun 3 | — |
| 6b | Apr 22 | — | May 6 – May 27 | — |
| 7a | Apr 16 | — | Apr 30 – May 21 | — |
| 7b | Apr 5 | — | Apr 19 – May 10 | — |
| 8a | Mar 29 | — | Apr 12 – May 3 | — |
| 8b | Mar 16 | — | Mar 30 – Apr 20 | — |
| 9a | Mar 3 | — | Mar 17 – Apr 7 | — |
| 9b | Feb 20 | — | Mar 6 – Mar 27 | — |
| 10a | Mar 2 | — | Mar 16 – Apr 6 | — |
Zone rows use the median frost dates of all ZIP codes in that zone. Zones measure winter cold, not season length, so two places in the same zone can have frost dates weeks apart — use your ZIP code for real dates.
When to plant sweet potatoes in major cities
| City | Median last frost | Transplant |
|---|---|---|
| Seattle, WA | Mar 13 | Mar 27 – Apr 17 |
| Portland, OR | Feb 25 | Mar 11 – Apr 1 |
| Salt Lake City, UT | Apr 25 | May 9 – May 30 |
| Denver, CO | Apr 30 | May 14 – Jun 4 |
| Minneapolis, MN | Apr 23 | May 7 – May 28 |
| Chicago, IL | Apr 10 | Apr 24 – May 15 |
| Detroit, MI | Apr 27 | May 11 – Jun 1 |
| Kansas City, MO | Apr 4 | Apr 18 – May 9 |
| Columbus, OH | Apr 20 | May 4 – May 25 |
| Boston, MA | Apr 4 | Apr 18 – May 9 |
| New York, NY | Mar 30 | Apr 13 – May 4 |
| Philadelphia, PA | Mar 30 | Apr 13 – May 4 |
| Washington, DC | Mar 29 | Apr 12 – May 3 |
| Charlotte, NC | Mar 30 | Apr 13 – May 4 |
| Nashville, TN | Apr 1 | Apr 15 – May 6 |
| Atlanta, GA | Mar 25 | Apr 8 – Apr 29 |
| Dallas, TX | Mar 2 | Mar 16 – Apr 6 |
Growing sweet potatoes: quick facts
| Frost tolerance | Very tender: damaged by frost and stalled by cold; plant once nights stay above 50°F |
|---|---|
| Soil temperature | at least 65°F at planting |
| Planting depth | slips set 3–4 in deep |
| Spacing | 12–18 in |
| Germination | — |
| Days to harvest | about 100 days from planting |
Typical figures from university extension planting guides. Seed packets give the best numbers for a specific variety.