Harvest guide
When to Plant Potatoes (Timing by Zone + Soil Temp)
Plant potatoes about 2 to 4 weeks before your last spring frost, once the soil warms to 45 F. That falls February to April in most US zones. In the South, a second crop goes in late summer for a fall dig.
Days to maturity
70–120days
Ready when
New: at flowering. Maincrop: 2-3 weeks after foliage dies back
The short answer
Plant potatoes about 2 to 4 weeks before your last spring frost, once the soil warms to 45 F at planting depth. In most US zones that lands February to April. The sprouts take a light frost but not a hard freeze. In the South, plant a second crop in late summer for a fall dig.
Potatoes are a cool-season crop you start in spring while the air is still chilly. The trick is the soil, not the calendar. Get a soil thermometer in the ground and wait for 45 F, and the timing falls into place from there.
This guide covers when to plant by zone, the soil-temperature cue that beats any date, and where a fall crop fits.
When to plant potatoes by USDA zone
The target is the same everywhere: plant 2 to 4 weeks before your last spring frost, once the soil hits 45 F. University of Maryland Extension puts the spring window at roughly March 15 to May 1, shifted earlier in the South and later in the North.
Colder zones thaw later, so they plant later. The windows below are starting points, not deadlines. Watch your own soil temperature and frost date.
| Region / zone | Typical spring window | Cue |
|---|---|---|
| Cold (zones 3–5) | April – early May | Soil reaches 45 F, 2–4 weeks before last frost |
| Temperate (zones 6–7) | March – April | Soil reaches 45 F, ground crumbles when worked |
| Warm/South (zones 8–9) | February – March | As soon as soil hits 45 F after the coldest weeks |
Cornell and Illinois Extension both set the soil-temperature floor at 40 F, while Ohio State, Maryland, and Georgia Extension lean to 45 F. Carry that as a range: 40 F is the bare minimum, 45 F is the safer target.
How to tell it is time to plant
The soil temperature is the real signal. A warm week in February tempts you, but the ground tells the truth.
Run down this checklist before you plant:
- Soil temperature at planting depth reads at least 45 F on a soil thermometer.
- The last spring frost is about 2 to 4 weeks out.
- A handful of soil crumbles apart instead of packing into a wet ball.
- The bed has drained and is no longer soggy from snowmelt or spring rain.
- Your seed potatoes have begun to chit, with short green sprouts at the eyes.
Pro tip
Chit your seed potatoes for 2 to 4 weeks before planting. Set them in a bright, cool spot (around 50 to 60 F) with the eyes facing up, in an egg carton or a shallow tray. Short, stubby green sprouts form, and those give the crop a head start once it hits the ground. Skip any seed potato that stays soft or fails to sprout.
Soil temperature beats the frost date
Lead with the soil thermometer, not the calendar. Air can warm up weeks before the ground does, and the seed piece only responds to the soil around it.
Illinois Extension is direct about the risk: seed pieces planted in damp, cold soil rot more easily, and March plantings can be frozen back by late frosts. Below 40 F the pieces sit and rot instead of sprouting.
The sprouts themselves are tougher than the seed pieces. University of Maryland Extension says potato plants withstand light frosts but not heavy frosts or freezing. So a light frost after the shoots emerge is survivable. A hard freeze is not.
Plant 3 to 5 inches deep, per UMD, with the seed pieces set in a furrow. The soil over them buffers the temperature and gives the sprouts room to push up.
Spring vs fall: a second crop in the South
Most US gardeners plant once, in spring. Warm southern zones get a second shot in late summer because potatoes finish best in cool weather, not summer heat.
| Planting | When | Best for |
|---|---|---|
| Spring | 2–4 weeks before last frost, soil at 45 F | Every US zone |
| Fall | About 14–16 weeks before first fall frost | Warm zones 8–9 (South) |
Texas A&M AgriLife Extension notes potatoes grow best in cool weather, which is why a late-summer planting matures through the cooler fall. For that fall crop, use small whole seed potatoes. Cut pieces are more likely to rot in warm soil than they are in cool spring ground.
Spacing stays the same for both crops. Set seed pieces about 12 inches apart in rows 30 inches apart, the layout in the potato spacing guide. Garlic follows the opposite rhythm, a fall planting for a summer dig, covered in when to plant garlic.
Common mistake
Planting too early into cold, wet soil is the costly error. The seed pieces do not sprout faster in 40 F mud, they rot. Skipping the soil thermometer and trusting a warm-week forecast is how a whole row fails to come up. Wait for 45 F and a bed that crumbles, even if the calendar says you are a week behind. A late start still beats replanting.
Your next step
Plant potatoes 2 to 4 weeks before your last spring frost, once the soil reads 45 F and crumbles in your hand. That lands February to April across most US zones, with a late-summer fall window in the South. Chit the seed potatoes first, set them 3 to 5 inches deep, and let a light frost pass without worry.
Once they are in the ground, the next milestone is the harvest. See when to harvest potatoes for the dig-day signs, from flowering for new potatoes to the tops dying back for storage spuds.
Common questions
What month do you plant potatoes?
It depends on your zone. Cold northern zones (3 to 5) plant in April or early May, once the soil reaches 45 F. Mild and southern zones (7 to 9) plant in February or March for a spring crop. The South can plant again in late summer for a fall harvest. The rule everywhere is the same: 2 to 4 weeks before your last spring frost.
Can you plant potatoes too early?
Yes. Seed potatoes pushed into cold, wet soil below 40 F often rot before they sprout. Illinois Extension warns that early plantings in damp, cold soil rot more easily, and that March plantings can be frozen back by late frosts. Wait until the soil reaches 45 F and crumbles in your hand instead of clumping.
What soil temperature do potatoes need to be planted?
Aim for a soil temperature of at least 45 F at planting depth. Cornell and Illinois Extension set the floor at 40 F, and Ohio State, Maryland, and Georgia Extension recommend about 45 F. Below 40 F the seed pieces sit and risk rotting rather than sprouting.
Can potatoes survive a frost after planting?
The sprouts handle a light frost but not a hard freeze. University of Maryland Extension says potato plants withstand light frosts but not heavy frosts or freezing. If a hard freeze threatens after the shoots are up, mound soil over them or cover the row overnight.
When can I plant a fall potato crop in the South?
In warm southern zones, plant a fall crop about 14 to 16 weeks before your first fall frost, usually in late summer. Texas A&M AgriLife Extension notes potatoes grow best in cool weather, so a late-summer planting matures through the cooler fall. Use small whole seed potatoes, which hold up better than cut pieces in warm soil.
Sources
Agronomic claims in this guide are checked against these primary sources.
- Potatoes — University of Maryland Extension
- Growing Guide - Potatoes — Cornell University Home Gardening
- Watch Your Garden Grow - Potato — University of Illinois Extension
- Irish Potatoes — Texas A&M AgriLife Extension
Keep reading
When to Harvest Potatoes (Signs They're Ready)
Dig new potatoes around flowering, about 6 to 8 weeks after planting. Wait for maincrop potatoes until the tops die back and the skin sets, roughly 90 to 120 days.
Read →When to Plant Garlic (Fall Timing by Zone)
Plant garlic in fall, about 3 to 6 weeks before the ground freezes, so roots set before winter. That lands mid-September to November across most US zones. Plant cloves 2 inches deep, pointy end up, 4 to 6 inches apart.
Read →When to Plant Zucchini (Frost + Soil Temp Timing)
Plant zucchini after your last spring frost, once the soil hits at least 60 F (ideally 65 to 70 F). Direct-sow seeds 1/2 to 1 inch deep, or set out transplants started 2 to 4 weeks earlier. Warm zones get a second fall crop.
Read →When to Plant Tomatoes (Frost + Soil Temp by Zone)
Set tomato transplants out 1 to 2 weeks after your last spring frost, once soil hits at least 60 F. Start seeds indoors 6 to 8 weeks before that frost date. Cold soil stalls them, so wait for warmth.
Read →When to Plant Swiss Chard (Spring and Fall Timing)
Plant swiss chard 2 to 4 weeks before your last spring frost, once the soil hits 40°F. Sow again 3 to 4 weeks before the first fall frost. Seeds go half an inch to an inch deep.
Read →When to Plant Sweet Potatoes (Soil Temp + Frost Timing)
Plant sweet potato slips 2 to 4 weeks after your last spring frost, once soil holds above 65°F. Get timing by zone, the soil-temp gate, and the mistake that rots slips in cold ground.
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