When to Plant Tomatoes in Stevens County, WA
Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.
Stevens County, Washington is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is September 24, giving you a growing season of approximately 137 days.
At an elevation of 1,751 feet, Stevens County receives approximately 24.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Tomatoes to ensure they mature before fall.
Stevens County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.3
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Tomatoes Planting Timeline — Stevens County, WA
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | May 24 | May 24 – Jun 7 |
| Direct Sow | May 17 | May 17 – Jun 7 |
| Harvest | July 26 | Jul 26 – Oct 4 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–85 days
Soil pH
6 – 7
USDA Zone
Zone 5b
Growing Season
137 days
Growing Tips for Stevens County
Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.
Tomatoes in Other Locations
Frequently Asked Questions
When should I plant Tomatoes in Stevens County, WA?
Stevens County is in Zone 5b with an average last frost of May 10. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Stevens County, WA?
Stevens County, Washington is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is September 24.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Stevens County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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