When to plant sweet potatoes in Fargo, North Dakota

May 24 – June 7

Transplant outdoors · typical Fargo year

Climate basis: NOAA station Fargo Hector INTL AP, ND (USW00014914), 1 mi (2 km) from downtown Fargo (ZCTA 58102 centroid), elevation 900 ft, on the 1991–2020 climate normals. Plant sweet potato slips from approximately the dates above, anchored to the median last spring 32°F freeze (May 10). One year in ten still freezes after May 23.

Last spring freezeMay 101-in-10 after May 23
First fall freezeSeptember 301-in-10 before Sep 18
Frost-free season143 daysmedian at 32°F
Hard freeze, 28°Apr 30Oct 10kills even hardy greens
USDA zone4a-30 to -25°F winter low not frost timing

The Fargo year

Transplant outdoorsMay 24 – Jun 7
  • indoors under lights
  • in the garden
  • frost-free season
  • 1-in-10 years still freeze to May 23
Sweet potatoes in Fargo · freeze context from Fargo Hector INTL AP, ND, 1991–2020 normals.

Every method, with its sources

Transplant outdoors

May 24 – Jun 7

Purdue: very tender (vegetatively propagated) — plant slips at least two weeks after the average last frost. Anchored to the median last spring freeze (May 10). Purdue University Extension

Start seeds indoors

Not calculated

The cited extension guides do not time an indoor seed-starting window for this crop.

Direct-sow outdoors

Not calculated

Sweet potatoes are grown from slips, not seed.

Fall planting

Not calculated

No source-backed fall planting rule exists for this crop in the registry, so no fall window is calculated.

Variety assumption: Assumes an average variety (about 100–120 days of warm weather from slips).

These windows describe typical years (1991–2020 climate normals), not this year's forecast. Freezes happen outside them — especially in frost pockets, valleys, and urban edges. Watch the forecast before committing tender plants.

This week, not a typical year:
Crop rule sources (1)

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