When to Plant Nasturtiums in North Dakota
Edible flowers that double as pest traps. Plant near vegetables to lure aphids away from your food crops.
The Short Answer
North Dakota Frost Dates
Your planting dates depend on which part of North Dakota you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Western North Dakota | 3b, 4a | May 15 - May 30 | Sep 10 - Sep 25 |
| Eastern North Dakota | 3a, 3b, 4a, 4b | May 10 - May 25 | Sep 15 - Sep 30 |
Nasturtiums Planting Schedule for North Dakota
Western North Dakota (Zones 3b, 4a)
Average last frost: May 15 - May 30 · Average first frost: Sep 10 - Sep 25
Eastern North Dakota (Zones 3a, 3b, 4a, 4b)
Average last frost: May 10 - May 25 · Average first frost: Sep 15 - Sep 30
Growing Nasturtiums in North Dakota
Nasturtiums in North Dakota's Climate
Nasturtiums add edible beauty to cold-climate gardens from June through frost. Direct sow after last frost — they grow fast in summer warmth. Plant near vegetables as companion and trap plants for aphids. The flowers and leaves have a peppery, watercress-like flavor that brightens salads.
Soil Considerations for North Dakota
Rich prairie soils — excellent for gardening. Alkaline in western regions. Heavy clay in Red River Valley. Make sure soil has warmed to at least 55°F before planting nasturtiums outside.
North Dakota Climate & Growing Season
Very cold winters. Short but warm summers with long days. Wind protection very important for gardens. Nasturtiums 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 North Dakota: Western North Dakota (3b, 4a) has a last frost around May 15 - May 30, while Eastern North Dakota (3a, 3b, 4a, 4b) sees frost end around May 10 - May 25. This difference matters for nasturtiums — transplant timing shifts by several weeks across the state.
Growing Tips
Both flowers and young leaves are edible with a peppery taste. Thrives in poor soil — too much nitrogen means all leaves, no flowers.
Companion Planting
Plant nasturtiums alongside these companions for better growth:
The Bottom Line
Last reviewed: March 29, 2026