When to Plant Potatoes in Zones 5-6 (2026)

Potatoes don’t follow the same “weeks before your last frost” rule as tomatoes or peppers. They grow from seed tubers, not tender seedlings, and a light frost on their early leaves rarely kills the plant. The real trigger is the soil, not the calendar.

The signal to watch

University of Minnesota Extension’s guide to growing potatoes is direct about it: plant seed pieces as soon as the soil warms. As one reference point, the guide gives early April for the Twin Cities area of Minnesota — useful as an example of what “as soon as the soil warms” looks like in one zone 5-6 location, not a date that applies everywhere in the band.

The source doesn’t give a specific soil-temperature number, so this guide won’t invent one. If your garden soil is workable — it crumbles rather than clumps when you squeeze it, and it’s no longer waterlogged from snowmelt — that’s the sign the extension guide is pointing at.

Worked example

Using the Twin Cities reference point: if your soil typically becomes workable in early April, that’s when seed pieces go in. From there, the source notes you can dig new, small potatoes about seven to eight weeks later — around late May to early June in that same example — and hill the plants again two weeks after planting as the shoots emerge.

Before you plant, check off