When to Plant Sweet Potatoes in Washington
Sweet potatoes are a warm-season root crop that produces nutritious, sweet tubers in orange, white, and purple varieties. They need a long, hot growing season.
Washington spans USDA hardiness zones 5b, 6a, 6b, 7a, 7b, 8a, 8b (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.
Find Your County
Click your county for exact Sweet Potatoes planting dates based on your local frost dates.
Hover over a county to see details. Click to view planting guide.
Sweet Potatoes Planting Calendar for Washington
▸ Zone 5b ~178 day growing season · Full guide →
Last frost: April 18 · First frost: October 13 · 178 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Direct Sow | April 25 | Apr 25 – May 16 |
| Harvest | August 1 | Aug 1 – Sep 19 |
▸ Zone 6a ~193 day growing season · Full guide →
Last frost: April 10 · First frost: October 20 · 193 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 13 | Feb 13 – Feb 27 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | July 24 | Jul 24 – Sep 11 |
▸ Zone 6b ~205 day growing season · Full guide →
Last frost: April 3 · First frost: October 25 · 205 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 6 | Feb 6 – Feb 20 |
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Direct Sow | April 10 | Apr 10 – May 1 |
| Harvest | July 17 | Jul 17 – Sep 4 |
▸ Zone 7a ~221 day growing season · Full guide →
Last frost: March 25 · First frost: November 1 · 221 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 4 | Feb 4 – Feb 18 |
| Transplant Outdoors | April 8 | Apr 8 – Apr 22 |
| Direct Sow | April 1 | Apr 1 – Apr 22 |
| Harvest | July 8 | Jul 8 – Aug 26 |
▸ Zone 7b ~235 day growing season · Full guide →
Last frost: March 18 · First frost: November 8 · 235 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 28 | Jan 28 – Feb 11 |
| Transplant Outdoors | April 1 | Apr 1 – Apr 15 |
| Direct Sow | March 25 | Mar 25 – Apr 15 |
| Harvest | July 1 | Jul 1 – Aug 19 |
▸ Zone 8a ~255 day growing season · Full guide →
Last frost: March 8 · First frost: November 18 · 255 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 18 | Jan 18 – Feb 1 |
| Transplant Outdoors | March 22 | Mar 22 – Apr 5 |
| Direct Sow | March 15 | Mar 15 – Apr 5 |
| Harvest | June 21 | Jun 21 – Aug 9 |
▸ Zone 8b ~276 day growing season · Full guide →
Last frost: February 25 · First frost: November 28 · 276 day season
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 7 | Jan 7 – Jan 21 |
| Transplant Outdoors | March 11 | Mar 11 – Mar 25 |
| Direct Sow | March 4 | Mar 4 – Mar 25 |
| Harvest | June 10 | Jun 10 – Jul 29 |
Growing Tips for Washington
Plant slips (rooted sprouts) after soil is thoroughly warm. Build raised mounds for better root development. Cure harvested roots at 80-85F for 10 days to develop sweetness.
Sweet Potatoes in Other States
- Alabama
- Alaska
- Alberta
- Arizona
- Arkansas
- British Columbia
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Manitoba
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Brunswick
- New Hampshire
- New Jersey
- New Mexico
- New York
- Newfoundland and Labrador
- North Carolina
- North Dakota
- Northwest Territories
- Nova Scotia
- Nunavut
- Ohio
- Oklahoma
- Ontario
- Oregon
- Pennsylvania
- Prince Edward Island
- Quebec
- Rhode Island
- Saskatchewan
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- West Virginia
- Wisconsin
- Wyoming
- Yukon
Frequently Asked Questions
When should I plant Sweet Potatoes in Washington?
Planting dates for Sweet Potatoes in Washington depend on your USDA zone. Washington spans zones 5b, 6a, 6b, 7a, 7b, 8a, 8b. Check the planting calendar above for your specific zone's frost dates and planting windows.
What zone is Washington for planting?
Washington contains USDA hardiness zones 5b, 6a, 6b, 7a, 7b, 8a, 8b. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.