When to Plant Sunflowers in Kansas
Few things bring more joy than a row of sunflowers turning their faces to the sun. Easy, dramatic, and pollinator-friendly.
The Short Answer
Kansas Frost Dates
Your planting dates depend on which part of Kansas you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Kansas | 5b, 6a | Apr 20 - May 5 | Oct 1 - Oct 15 |
| Central Kansas | 6a, 6b | Apr 10 - Apr 25 | Oct 10 - Oct 25 |
| Southern Kansas | 6b, 7a | Apr 1 - Apr 15 | Oct 15 - Nov 1 |
Sunflowers Planting Schedule for Kansas
Northern Kansas (Zones 5b, 6a)
Average last frost: Apr 20 - May 5 · Average first frost: Oct 1 - Oct 15
Central Kansas (Zones 6a, 6b)
Average last frost: Apr 10 - Apr 25 · Average first frost: Oct 10 - Oct 25
Southern Kansas (Zones 6b, 7a)
Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 15 - Nov 1
Growing Sunflowers in Kansas
Sunflowers in Kansas's Climate
Sunflowers are nearly foolproof in moderate climates. Direct sow after frost and watch them grow a foot or more per week in the summer heat. Succession plant every 2 weeks through late June for blooms all summer. Your reliable warm season gives even the tallest mammoth varieties plenty of time to mature.
Soil Considerations for Kansas
Prairie soils in east — rich and deep. More alkaline and thinner soils in west. Wind erosion can be an issue. Make sure soil has warmed to at least 55°F before planting sunflowers outside.
Kansas Climate & Growing Season
Hot summers with strong winds. Severe thunderstorms and hail risk. Drier in the west. Good growing conditions for heat-loving crops. Sunflowers 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 Kansas: Northern Kansas (5b, 6a) has a last frost around Apr 20 - May 5, while Southern Kansas (6b, 7a) sees frost end around Apr 1 - Apr 15. This difference matters for sunflowers — transplant timing shifts by several weeks across the state.
Growing Tips
Direct sow is preferred — sunflowers don't love transplanting. Succession plant every 2 weeks for blooms all summer.
Companion Planting
Plant sunflowers alongside these companions for better growth:
Keep sunflowers away from:
The Bottom Line
Last reviewed: March 29, 2026