When to plant pumpkins in North Dakota
North Dakota’s average last spring frost is May 15, and the first fall frost typically arrives around September 20 — about 128 frost-free days (USDA zones 3a, 3b, 4a, 4b). Pumpkin needs 90–120 days to mature, which fits comfortably within North Dakota's growing season.
When to plant pumpkins in North Dakota: the short answer
For a spring planting, plant out May 15 – Jun 1, with seeds started indoors Apr 17 – May 1. Wait until the soil is at least 60°F and frost is over. For Halloween, count back 90–120 days from September 20: sow by May 23–Jun 22. See the Halloween plan.
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow pumpkins in North Dakota, step by step
- Start seeds indoors (Apr 17 – May 1). Sow seeds 1 inch deep in seed-starting mix under bright light. They take 5-10 days to sprout, fastest in soil around 85°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. They need at least six to eight hours of direct sun a day and loose soil at least 18 inches deep, with a pH between 5.5 and 7.5. Dig in compost before planting.
- Plant out (May 15 – Jun 1). Space plants about 48 inches apart in rows 96 inches apart. It is killed by frost, so nothing goes outside until the danger has passed.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: squash vine borer, squash bug, striped cucumber beetle. Diseases and disorders: powdery mildew, bacterial wilt.
- Harvest (from about Aug 20 – Sep 19). Pumpkin takes 90-120 days to reach harvest. For Halloween pumpkins in the north, count back 100-120 days from 31 Oct and start indoors. Mini varieties can climb a strong trellis.
Figures come from our crop data; dates use North Dakota’s average frost dates. More in the full pumpkin growing guide.
Planting pumpkins in North Dakota for Halloween
Spring dates above suit a long season. If you want fruit ready for Halloween, count back from North Dakota's average first fall frost (September 20), which comes before Halloween. Pumpkin takes 90–120 days from sowing to a mature fruit, so these are the latest sowing dates. Sow earlier for a margin, but not too early: the University of Arkansas Extension warns that pumpkins planted too early may rot before Halloween.
| Days to maturity | Latest sowing for Halloween | Typical for |
|---|---|---|
| 120 days | May 23 | slowest types (giants) |
| 100 days | June 12 | jack-o'-lantern and pie types (University of Arkansas variety table) |
| 90 days | June 22 | quickest types |
See the full growing guide for pumpkin. Days to maturity vary by variety, so check the seed packet.
Pumpkin planting dates by USDA zone in North Dakota
North Dakota spans USDA zones 3a, 3b, 4a, 4b. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the pumpkin dates shift with them.
When to plant pumpkins in nearby states
| State | Last frost | Plant out |
|---|---|---|
| North Dakota (this page) | May 15 | May 15 – Jun 1 |
| South Dakota | May 10 | May 10 – May 27 |
| Nebraska | April 30 | Apr 30 – May 17 |
| Kansas | April 15 | Apr 15 – May 2 |
| Oklahoma | April 1 | Apr 1 – Apr 18 |
Questions gardeners in North Dakota ask
When is the best time to plant pumpkins in North Dakota?
Plant pumpkin transplants outdoors in North Dakota between May 15 and June 1. That timing is set by North Dakota's average last spring frost of May 15.
When should I start pumpkin seeds indoors in North Dakota?
Start seeds indoors between April 17 and May 1, about 3 weeks before the last frost, so the seedlings are ready to plant out from May 15.
What is the latest I can plant pumpkins in North Dakota?
About June 22. Pumpkins need at least 90 days to mature, and frost around September 20 ends the season, so later plantings risk being cut short. If you want ripe fruit for Halloween, the cut-off is earlier: see the Halloween dates on this page.
When will pumpkins planted in North Dakota be ready to harvest?
Planted on time, pumpkins are usually ready from about August 20 to September 19, 90-120 days after planting.
When should I plant pumpkins in North Dakota for Halloween?
Count back 90-120 days from September 20, North Dakota's average first fall frost, which comes before Halloween: the latest sowing dates are May 23 to June 22. Sow a little earlier for a margin.
When is the last frost in North Dakota?
On average around May 15, with the first fall frost around September 20 - about 128 frost-free days. Your town may differ by two weeks or more.