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When to Plant Sweet Corn in Washington

🌱

Direct Sow Outdoors

Friday, February 6, 2026

State

Washington

USDA Zones

5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b

Avg Last Frost

Friday, February 20, 2026

Cities Covered

488

Washington Planting Schedule by Zone

Washington spans 9 zones — find yours below for the most accurate dates.

Zone Last Frost Direct Sow
5b Saturday, April 25, 2026 Saturday, April 11, 2026
6a Monday, April 20, 2026 Monday, April 6, 2026
6b Wednesday, April 15, 2026 Wednesday, April 1, 2026
7a Friday, April 10, 2026 Friday, March 27, 2026
7b Sunday, April 5, 2026 Sunday, March 22, 2026
8a Friday, March 20, 2026 Friday, March 6, 2026
8b Sunday, March 15, 2026 Sunday, March 1, 2026
9a Friday, February 20, 2026 Friday, February 6, 2026
9b Tuesday, February 10, 2026 Tuesday, January 27, 2026

Dates based on average last frost. Check your local forecast before planting.

🌿 About Sweet Corn

Scientific Name Zea mays var. saccharata
Days to Maturity 75 days
Plant Type Stalk
Sun Full Sun (8+ hours)
Water High (consistent moisture, especially at silking)
Spacing 12" apart

🤝 Companion Plants for Sweet Corn

Good Companions

BeanSquashCucumberPeaMelon

Avoid Planting Near

Tomato
See the full companion planting guide for Sweet Corn →

Growing Sweet Corn in Washington: Complete Guide

Sweet Corn (Zea mays var. saccharata) is a crop that grows best when sown directly in the garden. In Washington, the right time to direct sow is around Friday, February 6, 2026, once soil temperatures are consistently warm enough for germination.

Because Washington stretches across 9 USDA hardiness zones (5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b), planting windows can shift by as much as six to eight weeks from one end of the state to the other. Gardeners in the warmer southern zones can start earlier, while those in cooler northern zones should wait until the zone table above shows their last frost has passed.

With 75 days to maturity, Sweet Corn fits comfortably within Washington's growing season in most zones. In the warmest parts of the state, a second planting later in the season may be possible.

Sweet Corn requires full sun (8+ hours) and high (consistent moisture, especially at silking) moisture. Most of Washington receives adequate sunlight during the growing season, though gardeners in humid eastern regions should watch for fungal issues and ensure good air circulation.

For the most precise planting dates tailored to your exact location, enter your ZIP code on our planting calendar or use the zone table above to find the schedule for your area of Washington.

Growing Sweet Corn in Washington: Local Tips

Climate-specific advice for Washington gardeners.

Choose short-season hybrids

Western Oregon and Washington don't accumulate enough heat units for most sweet corn; choose varieties bred for cool climates (Butterfruit Early, Polar Vee) and plant in the warmest spot in the garden.

Frequently Asked Questions

When should I plant Sweet Corn in Washington?

In Washington, direct sow Sweet Corn outdoors around Friday, February 6, 2026. Washington spans zones 5b–9b, so gardeners in warmer zones can plant earlier.

What is the last frost date in Washington?

Washington spans 9 USDA zones (5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b), so last frost dates vary by region. Boyds (5b) sees frost until around Saturday, April 25, 2026, while Tokeland (9b) is frost-free much earlier.

How long does Sweet Corn take to grow in Washington?

Sweet Corn takes about 75 days from transplant (or direct sow) to harvest. In Washington's longer-season zones, a second planting in late summer may be possible.

What USDA zones does Washington cover for Sweet Corn?

Washington includes zones 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b. Sweet Corn grows well across all of these zones with adjusted timing — use the zone table above to find the right dates for your part of the state.

Find Precise Dates for Your City

Select a city for exact planting dates based on local frost records.

Other Plants for Washington

When to Plant Sweet Corn in Other States