When to Plant Cucumbers in Iowa
Cool, crisp, and perfect for salads and pickling. Cucumbers thrive in warm weather and produce abundantly.
The Short Answer
Iowa Frost Dates
Your planting dates depend on which part of Iowa you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Iowa | 4b, 5a | May 5 - May 20 | Sep 20 - Oct 5 |
| Central Iowa | 5a, 5b | Apr 25 - May 10 | Oct 1 - Oct 15 |
| Southern Iowa | 5b | Apr 20 - May 5 | Oct 5 - Oct 20 |
Cucumbers Planting Schedule for Iowa
Northern Iowa (Zones 4b, 5a)
Average last frost: May 5 - May 20 · Average first frost: Sep 20 - Oct 5
Central Iowa (Zones 5a, 5b)
Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15
Southern Iowa (Zones 5b)
Average last frost: Apr 20 - May 5 · Average first frost: Oct 5 - Oct 20
Growing Cucumbers in Iowa
Cucumbers in Iowa's Climate
Cucumbers need warmth but mature quickly — 50-60 day varieties fit comfortably within your growing season. Start seeds indoors 3 weeks before last frost and transplant after soil reaches 60°F. Black plastic mulch warms soil for earlier transplanting. Row cover adds warmth during cool June nights. Choose cold-tolerant varieties like Marketmore and pick frequently to keep plants producing.
Soil Considerations for Iowa
Outstanding black prairie soils. Some of the richest agricultural land in the world. Minimal amendment needed. Make sure soil has warmed to at least 60°F before planting cucumbers outside.
Iowa Climate & Growing Season
Continental climate. Cold winters, warm humid summers. Good growing season with adequate rainfall. Cucumbers 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 Iowa: Northern Iowa (4b, 5a) has a last frost around May 5 - May 20, while Southern Iowa (5b) sees frost end around Apr 20 - May 5. This difference matters for cucumbers — transplant timing shifts by several weeks across the state.
Growing Tips
Trellis for straighter fruits and better air circulation. Pick regularly to encourage more production.
Companion Planting
Plant cucumbers alongside these companions for better growth:
Keep cucumbers away from:
The Bottom Line
Last reviewed: March 29, 2026