Tennessee · zones 7a–8a
When to plant potatoes in Tennessee.
Sow between Mar 1 to Apr 3 in a typical year, keyed to Tennessee's median last frost around Apr 8. A second, fall sowing fits Jul 7 to Jul 20. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Potatoes dates for a typical Tennessee season.
Direct sow
Mar 1 to Apr 3
Keyed to the ~Apr 8 last frost. Sow 4" deep, 12" apart.
Fall round
Jul 7 to Jul 20
Counted back from the ~Oct 25 first frost.
Harvest
~90 days later
~3 lb per plant over ~1 weeks.
Tennessee spans more than one climate: Zone 7 is the most common zone, but the state runs 7a to 8a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
Tennessee growing notes
Hill differently depending on which side of Tennessee you're digging.
Bottomland silt, Basin clay, ridge rock
West Tennessee's Mississippi bottomland gives potatoes silt so loose a tuber swells outward with nothing pushing back, which is part of why the region once grew a serious commercial potato crop, though today's acreage is a small fraction of that history. Middle Tennessee's Nashville Basin runs a heavier, more clay-rich profile over its limestone base, fertile but slower to warm and quicker to compact into a crust after a hard rain. East Tennessee's ridge and valley country adds a third variable: soil depth that can shrink to almost nothing within a few feet where a garden runs up against exposed rock.
In the Basin's heavier clay or on East Tennessee's shallow ridge ground, hilling matters more than it does in the loose bottomland, since a shallow hill in compacted soil still leaves developing tubers close enough to the surface to green in the sun. Build the hill up four to six inches around the stem with each pass in either of those regions, checking that no tuber shows daylight through the covering soil, and repeat the hilling a second time about three weeks later as the plant continues to grow.
Scab is a pH problem you can see coming
Potato scab raises rough, corky patches on the skin without hurting the eating quality underneath, and keeping soil pH at 5.2 or lower is the single reliable way to stop the disease before it ever gets started. That number is worth checking specifically before planting, since a general fertility test with a broad pH range can miss exactly the threshold that matters here. Tennessee's Basin soils, drawing on limestone bedrock, often run naturally higher than that comfort zone, while more acidic East Tennessee mountain soils may already sit low enough without any adjustment.
Where a soil test comes back above that 5.2 line, sulfur worked into the row ahead of planting is the standard fix, though it takes a full season to shift pH meaningfully, so plan a year ahead rather than expecting a quick correction right before you plant. Let cut seed potato pieces sit somewhere cool and shaded rather than planting them wet from the knife; press a thumbnail into the cut face before you plant, and if it dents easily it is not ready, since only a surface that resists like dry skin has sealed enough to shrug off rot in Tennessee's humid soil.
Early blight, not late, is your summer threat
Potato foliage in a Tennessee summer falls victim to early blight, not late: dark spots ringed like a target, starting on the lowest, oldest leaves and working upward as the season goes. Late blight needs cool days in the 60s and 70s to spread, and it stops making headway once afternoons climb into the mid 90s, so the disease that shows up on northern potato fields in July simply cannot get going here until the weather turns again in fall. Watch those bottom leaves the way you would watch a gauge, since old growth going first is the tell that separates real disease from a plant simply finishing out the season.
Give the row enough width that you can walk the line without brushing foliage on either side, so it dries between rows after every rain, and avoid overhead watering in the evening, since wet leaves sitting through a warm, humid night are exactly the setup blight spores need to germinate. Colorado potato beetle rounds out the watch list here, typically running two generations through a Tennessee season; check the underside of leaves for its bright yellow-orange egg clusters starting as soon as plants emerge.
In Tennessee: watch for
The pests that find potatoes here.
A middle-length season, about 200 frost-free days, means potato overlaps colorado potato beetle for a stretch each summer. Check plants every week or two and treat early.
Striped beetles and orange grubs eating the leaves.
Organic fix: Handpick adults, crush the orange egg clusters, dust with diatomaceous earth.
Dark greasy blotches after cool, wet spells.
Organic fix: Pull infected plants fast, keep leaves dry, use neem as a preventive.
Common scab
Rough, corky patches on the skin, raised on some tubers and sunk into pits on others.
Organic fix: Keep the bed evenly moist through the weeks right after tubers set, rotate away from potatoes, and pick a scab-resistant variety next time.
Your season math: Tennessee gives potatoes about 200 frost-free days, and it needs roughly 90 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting potatoes in Tennessee: questions
When should I plant potatoes in Tennessee?+
In a typical Tennessee year, sow potatoes between Mar 1 to Apr 3, keyed to the state's median last frost around Apr 8. There's also a fall window: Jul 7 to Jul 20. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Tennessee?+
Tennessee spans zones 7a–8a, mostly zone 7. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many potatoes plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.