When to Plant Tomatoes in Fremont County, ID
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.
Fremont County, Idaho is in USDA Zone 4b. The average last spring frost is June 12 and the first fall frost is September 6, giving you a growing season of approximately 86 days.
At an elevation of 5,282 feet, Fremont County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Tomatoes to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Tomatoes successfully. Mulch heavily to conserve soil moisture.
Fremont County Soil Profile
Soil Type
Loam
Soil pH
6.4-8
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Tomatoes Planting Timeline — Fremont County, ID
Tomatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 10 | Apr 10 – Apr 24 |
| Transplant Outdoors | July 3 | Jul 3 – Jul 17 |
| Direct Sow | June 26 | Jun 26 – Jul 17 |
| Harvest | September 4 | Sep 4 – Nov 13 |
Plant 0.5" deep · 24" apart · Rows 36" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| 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 4b
Growing Season
86 days
Growing Tips for Fremont 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 Fremont County, ID?
Fremont County is in Zone 4b with an average last frost of June 12. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fremont County, ID?
Fremont County, Idaho is in USDA Hardiness Zone 4b. The average last spring frost is June 12 and first fall frost is September 6.
Plan Your Garden with Confidence
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