When to plant / Potatoes
When to plant potatoes
Plant potatoes up to 2 weeks before the last spring frost. Potatoes are a semi-hardy crop in Colorado State University Extension's planting guide, and that is the guide's rule for the class. Across the 39 U.S. cities on this site the window opens between Jan 26 (Sacramento, CA) and Apr 29 (Concord, NH), because each city's own NOAA last-frost date is different.
The planting rule for potatoes, in plain words
Colorado State's Vegetable Planting Guide sorts vegetables into four frost classes and gives each class one timing rule relative to the average last spring frost. Potatoes sit in the semi-hardy class, whose rule reads: As early as 0-2 weeks before the date of the average last spring frost.
On this site that becomes -2 to 0 weeks from the station's 50% probability last 32°F date, the same arithmetic every city calendar uses.
Potatoes go in as seed pieces, not seed or transplants, so there is no indoor date. Typical days to harvest in the guide: 125.
Soil temperature for potatoes
Minimum soil temperature for potatoes in the cited sources: 45°F (minimum germination soil temperature). A frost date cannot see the soil, so take a morning reading before trusting the window; the soil temperature guide covers every crop.
Potatoes: planting dates for 39 U.S. cities
The rule above applied to each station's own NOAA normals, earliest first. City links open that station's full calendar.
| City | Last spring frost (32°F) | Plant seed potatoes | Last fall planting |
|---|---|---|---|
| Sacramento, CA | Feb 9 | Jan 26 – Feb 9 | Aug 7 |
| Houston, TX | Feb 18 | Feb 4 – Feb 18 | Aug 12 |
| Austin, TX | Feb 19 | Feb 5 – Feb 19 | Aug 10 |
| San Antonio, TX | Mar 1 | Feb 15 – Mar 1 | Aug 5 |
| Dallas–Fort Worth, TX | Mar 8 | Feb 22 – Mar 8 | Jul 30 |
| Seattle, WA | Mar 8 | Feb 22 – Mar 8 | Jul 26 |
| Portland, OR | Mar 16 | Mar 2 – Mar 16 | Jul 22 |
| Atlanta, GA | Mar 20 | Mar 6 – Mar 20 | Jul 26 |
| Birmingham, AL | Mar 27 | Mar 13 – Mar 27 | Jul 17 |
| Oklahoma City, OK | Mar 27 | Mar 13 – Mar 27 | Jul 14 |
| Washington, DC | Mar 28 | Mar 14 – Mar 28 | Jul 22 |
| New York City | Apr 1 | Mar 18 – Apr 1 | Jul 23 |
| Philadelphia, PA | Apr 2 | Mar 19 – Apr 2 | Jul 15 |
| Louisville, KY | Apr 3 | Mar 20 – Apr 3 | Jul 9 |
| Raleigh, NC | Apr 3 | Mar 20 – Apr 3 | Jul 9 |
| St. Louis, MO | Apr 3 | Mar 20 – Apr 3 | Jul 8 |
| Charlotte, NC | Apr 4 | Mar 21 – Apr 4 | Jul 8 |
| Richmond, VA | Apr 4 | Mar 21 – Apr 4 | Jul 9 |
| Boston, MA | Apr 6 | Mar 23 – Apr 6 | Jul 13 |
| Nashville, TN | Apr 6 | Mar 23 – Apr 6 | Jul 7 |
| Kansas City, MO | Apr 12 | Mar 29 – Apr 12 | Jun 27 |
| Columbus, OH | Apr 16 | Apr 2 – Apr 16 | Jul 1 |
| Indianapolis, IN | Apr 16 | Apr 2 – Apr 16 | Jun 26 |
| Des Moines, IA | Apr 17 | Apr 3 – Apr 17 | Jun 21 |
| Detroit, MI | Apr 20 | Apr 6 – Apr 20 | Jun 28 |
| Omaha, NE | Apr 21 | Apr 7 – Apr 21 | Jun 15 |
| Salt Lake City, UT | Apr 21 | Apr 7 – Apr 21 | Jun 28 |
| Chicago, IL | Apr 22 | Apr 8 – Apr 22 | Jun 23 |
| Cleveland, OH | Apr 22 | Apr 8 – Apr 22 | Jul 5 |
| Hartford, CT | Apr 24 | Apr 10 – Apr 24 | Jun 17 |
| Pittsburgh, PA | Apr 24 | Apr 10 – Apr 24 | Jun 24 |
| Minneapolis, MN | Apr 25 | Apr 11 – Apr 25 | Jun 14 |
| Albany, NY | Apr 28 | Apr 14 – Apr 28 | Jun 14 |
| Grand Rapids, MI | Apr 28 | Apr 14 – Apr 28 | Jun 20 |
| Portland, ME | May 1 | Apr 17 – May 1 | Jun 14 |
| Madison, WI | May 2 | Apr 18 – May 2 | Jun 9 |
| Burlington, VT | May 4 | Apr 20 – May 4 | Jun 12 |
| Denver, CO | May 6 | Apr 22 – May 6 | Jun 10 |
| Concord, NH | May 13 | Apr 29 – May 13 | no separate fall sowing |
Fall column: 125 days to harvest counted back from the first fall 32°F date, plus a 7-day allowance for the semi-hardy class that is this site's own assumption (Purdue HO-66-W method, methodology).
3 frost-free stations are left out. Not in the table? The planner takes any pair of frost dates.
Three cities, one rule
- Sacramento, California — last spring frost Feb 9, so plant seed potatoes Jan 26 – Feb 9. 297 frost-free days in all.
- Kansas City, Missouri — last spring frost Apr 12, so plant seed potatoes Mar 29 – Apr 12. 194 frost-free days in all.
- Concord, New Hampshire — last spring frost May 13, so plant seed potatoes Apr 29 – May 13. 140 frost-free days in all.
Questions about planting potatoes
When should I plant potatoes outside?
Potatoes are a semi-hardy crop, so Colorado State Extension's rule is up to 2 weeks before the last spring frost. In Sacramento, CA that is Jan 26 – Feb 9; in Concord, NH it is Apr 29 – May 13. Find your city in the table above, or enter your own frost date in the planner.
Can I start potatoes indoors?
Potatoes are planted directly in the garden on this site's calendars, following the Colorado State guide, so no indoor date is computed. The outdoor window for Kansas City, MO is Mar 29 – Apr 12.
What soil temperature do potatoes need?
The minimum germination soil temperature in Colorado State Extension's guide is 45°F. The frost window is the earliest the crop is safe from freezing; the soil reading tells you whether it will actually grow. Measure at 4 inches in the morning before planting.
How long do potatoes take to harvest?
Colorado State's typical days to harvest for this row is 125 days. Compare that to your city's frost-free days in the table: Sacramento, CA has 297, Concord, NH has 140.
Can I plant potatoes for a fall harvest?
38 of the 39 cities in the table show a separate fall planting date for potatoes, found by counting the days to harvest back from the first fall frost. Where the row says no separate fall sowing, the spring window already covers the season.
Related planting dates
- When to plant onions — 2 to 4 weeks before the last spring frost
- When to plant garlic — 1 to 2 weeks after the first fall frost
- When to plant tomatoes — 2 to 4 weeks after the last spring frost
- All crops · calendars by city · cool-season vs warm-season crops
Sources for this page
| Source | Used for | Read |
|---|---|---|
| NOAA/NCEI U.S. Climate Normals 1991–2020 | 50% probability last spring and first fall 32°F and 28°F dates for each station | 2026-10-16 |
| Colorado State University Extension, CMG GardenNotes #720 Vegetable Planting Guide | spring class rules, transplant age and days to harvest, via crops.json | 2026-10-16 |
| Colorado State University Extension, Vegetable Planting Guide (germination soil temperature table) | figures as quoted in this site's soil-temperature guide (/blog/soil-temperature-for-planting-vegetables/); the page could not be re-fetched on 2026-10-23 and the 2026-10-17 reading stands; the same minimum germination figures (tomato 50, pepper 60, potato 45, onion 35, cucumber and summer squash 60°F, read at 8 a.m. at 4 inches) appear in the soil temperature table of CMG GardenNotes #720, re-read 2026-10-23 | 2026-10-17 |
Every date in the table is arithmetic on the station's NOAA normal and the offset stated by the source; the quoted sentences are the only figures on this page that are not computed. Normals are 30-year averages and describe the station, not your yard. Rules checked 2026-10-23; see the methodology page.