When to plant sweet potatoes in Minneapolis, Minnesota

May 7 – May 21

Transplant outdoors · typical Minneapolis year

Climate basis: NOAA station Lower St Anthony Falls, MN (USC00214884), 1 mi (2 km) from downtown Minneapolis (ZCTA 55401 centroid), elevation 754 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 (April 23). One year in ten still freezes after May 7.

Last spring freezeApril 231-in-10 after May 7
First fall freezeOctober 161-in-10 before Oct 2
Frost-free season175 daysmedian at 32°F
Hard freeze, 28°Apr 14Oct 27kills even hardy greens
USDA zone5a-20 to -15°F winter low not frost timing

The Minneapolis year

Transplant outdoorsMay 7 – May 21
  • indoors under lights
  • in the garden
  • frost-free season
  • 1-in-10 years still freeze to May 7
Sweet potatoes in Minneapolis · freeze context from Lower St Anthony Falls, MN, 1991–2020 normals.

Every method, with its sources

Transplant outdoors

May 7 – May 21

Purdue: very tender (vegetatively propagated) — plant slips at least two weeks after the average last frost. Anchored to the median last spring freeze (Apr 23). 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)

Keep exploring