When to Plant Beans (Green/Snap) in Idaho
Easy, productive, and they even improve your soil by fixing nitrogen. A perfect crop for beginners.
The Short Answer
Idaho Frost Dates
Your planting dates depend on which part of Idaho you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Idaho | 5a, 5b, 6a | May 5 - May 25 | Sep 15 - Oct 5 |
| Boise Area | 6b, 7a | Apr 20 - May 5 | Oct 5 - Oct 20 |
| Eastern Idaho | 3b, 4a, 4b, 5a | May 20 - Jun 10 | Sep 1 - Sep 20 |
Beans (Green/Snap) Planting Schedule for Idaho
Northern Idaho (Zones 5a, 5b, 6a)
Average last frost: May 5 - May 25 · Average first frost: Sep 15 - Oct 5
Boise Area (Zones 6b, 7a)
Average last frost: Apr 20 - May 5 · Average first frost: Oct 5 - Oct 20
Eastern Idaho (Zones 3b, 4a, 4b, 5a)
Average last frost: May 20 - Jun 10 · Average first frost: Sep 1 - Sep 20
Growing Beans (Green/Snap) in Idaho
Beans (Green/Snap) in Idaho's Climate
Beans are one of the most reliable warm-season crops for cold climates because they grow fast and mature quickly. Direct sow when soil reaches 60°F — typically late May to early June. Bush types produce a concentrated harvest in 50-55 days, which fits easily within even 100-day growing seasons. Pole types produce over a longer window but need more time to begin bearing.
Soil Considerations for Idaho
Volcanic ash soils in south — excellent for gardening. Rocky soils in mountains. Alkaline in many areas. Make sure soil has warmed to at least 60°F before planting beans (green/snap) outside.
Idaho Climate & Growing Season
Arid climate. Low humidity. Hot days and cool nights. Irrigation essential. Short season at higher elevations. Beans (Green/Snap) cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.
Growing season length varies across Idaho: Northern Idaho (5a, 5b, 6a) has a last frost around May 5 - May 25, while Eastern Idaho (3b, 4a, 4b, 5a) sees frost end around May 20 - Jun 10. This difference matters for beans (green/snap) — transplant timing shifts by several weeks across the state.
Growing Tips
Direct sow only — beans don't transplant well. Inoculate seeds with rhizobium for better nitrogen fixation.
Companion Planting
Plant beans (green/snap) alongside these companions for better growth:
Keep beans (green/snap) away from:
The Bottom Line
Last reviewed: March 29, 2026