When to plant potatoes in Washington
Washington spans USDA hardiness zones 4a-9a. Average last spring frost: 04-15 (W) to 05-25 (E). This calendar gives you the indoor start, transplant, and direct-sow dates for Solanum tuberosum.
Washington planting dates for potatoes
Dates for Washington vary significantly by region. Use the average frost date lookup for your specific ZIP code, then apply the standard offsets: direct sow 2 weeks before last frost.
Why these dates
Potatoes are cool-season but frost-sensitive. Plant seed potatoes 2-3 weeks before last frost when soil reaches 45-50F at 4 inches deep.
The dates above are anchored to Washington's average last spring frost date of 04-15 (W) to 05-25 (E), with offsets standard across university Extension publications. For zone-specific local timing, use the frost date lookup tool with your ZIP code.
More on growing potatoes
The full growing guide for potatoes - varieties, soil, fertilization, pests, harvest, storage - is here: Potatoes growing guide.
More Washington planting information
- Full Washington planting calendar (all crops + ornamentals)
- Find your exact USDA zone by ZIP
- Look up your average frost dates
- Seed starting timeline calculator