When to Plant Sweet Potatoes in Missouri
Not related to regular potatoes at all. Sweet potatoes need heat and a long growing season but reward with incredible harvests.
The Short Answer
Missouri Frost Dates
Your planting dates depend on which part of Missouri you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Missouri | 5b, 6a | Apr 20 - May 5 | Oct 1 - Oct 15 |
| Central Missouri | 6a, 6b | Apr 10 - Apr 25 | Oct 10 - Oct 25 |
| Southern Missouri | 6b, 7a | Apr 1 - Apr 15 | Oct 15 - Nov 1 |
Sweet Potatoes Planting Schedule for Missouri
Northern Missouri (Zones 5b, 6a)
Average last frost: Apr 20 - May 5 · Average first frost: Oct 1 - Oct 15
Central Missouri (Zones 6a, 6b)
Average last frost: Apr 10 - Apr 25 · Average first frost: Oct 10 - Oct 25
Southern Missouri (Zones 6b, 7a)
Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 15 - Nov 1
Growing Sweet Potatoes in Missouri
Sweet Potatoes in Missouri's Climate
Sweet potatoes are achievable in your climate with effort. Plant slips in late May to early June when soil reaches 65°F. Black plastic mulch is essential for warming soil. Choose 90-day varieties only. Harvest before first frost — this is critical because even light frost damages tubers. Your window is tight but workable.
Soil Considerations for Missouri
Rich loess soils along Missouri River. Rocky Ozark soils in south. Heavy clay common. Generally fertile. Loose, well-drained soil is especially important for sweet potatoes since the edible portion grows underground. If your soil is heavy clay, consider raised beds.
Missouri Climate & Growing Season
Continental climate. Hot, humid summers. Four seasons. Good growing season in most of state. Sweet Potatoes 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 Missouri: Northern Missouri (5b, 6a) has a last frost around Apr 20 - May 5, while Southern Missouri (6b, 7a) sees frost end around Apr 1 - Apr 15. This difference matters for sweet potatoes — transplant timing shifts by several weeks across the state.
Growing Tips
Grow from slips, not seeds. Start slips from a sweet potato in water 8 weeks before transplanting. Cure harvested tubers in warmth for 10 days.
Companion Planting
Plant sweet potatoes alongside these companions for better growth:
Keep sweet potatoes away from:
The Bottom Line
Last reviewed: March 29, 2026