Mississippi · zones 8a–9a
When to plant sweet corn in Mississippi.
Sow between Mar 20 to Jun 19 in a typical year, keyed to Mississippi's median last frost around Mar 13. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Sweet Corn dates for a typical Mississippi season.
Direct sow
Mar 20 to Jun 19
Keyed to the ~Mar 13 last frost. Sow 1.5" deep, 12" apart.
Harvest
~75 days later
~1 lb per plant over ~1 weeks.
Mississippi spans more than one climate: Zone 8 is the most common zone, but the state runs 8a to 9a. 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.
Mississippi growing notes
Sweet corn in Mississippi is a math problem worth solving.
Why succession sowing beats one big spring planting
Corn matures all at once. A single planting ripens within a few days across the whole block, hands you a week of corn, and then it is done, which is why staggering sowings works better than one big spring planting. Start new rows every 10 to 14 days through the spring window instead, and you trade one glut for a steady supply that actually gets eaten fresh.
Isolation matters as much as timing if you grow more than one type. Different sweet corn varieties, and especially any field corn nearby, cross-pollinate on the wind, and a stray cross shows up as tough, starchy kernels scattered through an otherwise sweet ear. Keep different types either 250 feet apart or staggered so their pollen-shed windows miss each other by at least 2 weeks.
The earworm trick every extension office repeats
Corn earworm is the pest that ends up inside the ear itself, entering through the silk and feeding down toward the kernels before anyone notices. Mississippi's warm, humid summers keep multiple generations active through the growing season, so relying on a single early spray misses the later broods entirely.
The reliable home fix is mineral oil, timed to each ear's own silk rather than the whole row on a single day: wait until that ear's silk turns from fresh green to wilted and brown, typically 5 to 8 days after it first shows and never sooner than 3, then place a few drops from an eyedropper or small syringe right at the tip where the silks bunch. Oil dropped on silk that is still green blocks pollen instead of the worm and leaves a bare, kernelless tip, so treat one ear as its own silk finishes browning rather than dosing every ear in the row at once.
Feed it heavy, then anchor it against wind
Sweet corn is a genuinely hungry crop, and Mississippi's warm season burns through soil nitrogen fast. Side-dress with a nitrogen-rich fertilizer once plants reach knee height and again when tassels first appear; corn that yellows from the bottom leaves upward partway through the season is telling you it ran out between feedings.
Plant corn in blocks of at least 4 short rows rather than one long row, both for the pollination coverage that gives full ears and for wind resistance. Mississippi's summer thunderstorms bring gusts that can lodge, meaning topple, a thin single row of corn overnight; hilling a couple inches of soil around the base of each stalk once plants are knee-high adds real anchoring against that.
In Mississippi: watch for
The pests that find sweet corn here.
With about 241 frost-free days, sweet corn spends longer in the ground here than in most of the country, which widens the window in which corn earworm can find it. Scout weekly from midseason and act on the first signs.
Caterpillars feeding down in the tip of the ear.
Organic fix: A few drops of oil on the silk; Bt on the silks.
Broken tassels and frass-filled holes in the stalk.
Organic fix: Bt on young plants; cut and destroy stalks after harvest.
Clusters on the tassels and upper leaves.
Organic fix: Usually minor; insecticidal soap if heavy.
Fall armyworm
Ragged holes through the unfurling whorl leaves, with sawdust-like droppings down in the funnel.
Organic fix: Check whorls weekly before tassel; Bt or spinosad while the caterpillars are still small.
Cinnamon-brown powdery pustules breaking out on BOTH sides of the same leaf, lower leaves first, darkening as they age.
Organic fix: Water at the ground rather than overhead, and choose resistant varieties next season; sprays are rarely worth it.
Your season math: Mississippi gives sweet corn about 241 frost-free days, and it needs roughly 75 days to a first harvest. That fits about 17 re-sown rounds across the season, so you can keep it coming instead of picking once.
Planting sweet corn in Mississippi: questions
When should I plant sweet corn in Mississippi?+
In a typical Mississippi year, sow sweet corn between Mar 20 to Jun 19, keyed to the state's median last frost around Mar 13. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Mississippi?+
Mississippi spans zones 8a–9a, mostly zone 8. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many sweet corn 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.