Mississippi planting calendar

When to plant onions in Mississippi — sow, transplant & harvest dates

Mississippi is mostly USDA zone 8b (range 7b-9a). Dates below are derived from onions's frost tolerance and Mississippi's frost window — not generic national averages.

Onions planting timetable for Mississippi

Stage	When in Mississippi	Anchor
Start seeds indoors	mid-January (January 14)	10 weeks before the last frost (late March)
Transplant outside	late February (February 25)	28 days before the last frost (late March)
First harvest (estimate)	mid-June (June 15)	~110 days from transplant

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Mississippi's climate shifts the onions dates

Mississippi's last spring frost averages late March and first fall frost early November, which sets the whole planting clock. Mississippi has a hot, humid, long season with mild winters. The Gulf Coast is nearly frost-free; the north sees a short cold spell. Sow early — onions bolt once daytime temperatures hold above 24 °C, so the earlier they go in, the longer the harvest.

Onions are day-length sensitive: long-day varieties (zones 1–6) begin bulbing when days exceed 14 hours, short-day types (zones 7–10) bulb at 10–12 hours, and intermediate-day varieties span zones 5–6. Start seeds indoors 10–12 weeks before the last spring frost and transplant out 4–6 weeks before it — young onion seedlings tolerate frost down to about -6 °C once hardened off. In zones 8–10 a second planting from sets in autumn is common, overwintering for an early-summer harvest.

Frost-risk note

Don't plant before late March — a hard freeze can still set young plants back. In the northern hill country near Tupelo (zone 7b) the safe date runs a week or two later.

Regional variation within Mississippi

the northern hill country near Tupelo (zone 7b) runs roughly 1-2 weeks behind the state average; the Gulf Coast around Gulfport (zone 9a) can plant 1-2 weeks earlier.

Jackson — USDA zone 8b
Gulfport — USDA zone 9a
Hattiesburg — USDA zone 8b
Tupelo — USDA zone 8a

What else to plant in Mississippi around then

The same early window suits peas, lettuce, spinach, and onion sets.

Quick-grow guide

Sun: Full sun — 6+ hours direct.
Soil temperature for germination: 10-35 °C (50-95 °F).
Spacing: 4-6 inches (10-15 cm) between plants.
Days to harvest: ~110 days from planting out.

Frequently asked questions

When is the best time to plant onions in Mississippi?

In Mississippi (mostly USDA zone 8b), sow onions indoors around mid-January, transplant outdoors late February (before the last frost, late March), and harvest from mid-June. Onions are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

What USDA zone is Mississippi?

Most of Mississippi sits in USDA hardiness zone 8b, with the state spanning roughly 7b-9a from the northern hill country near Tupelo (zone 7b) to the Gulf Coast around Gulfport (zone 9a). The last spring frost averages late March and the first fall frost early November.

Can you grow onions in Mississippi?

Yes. Mississippi's dominant zone 8b supports onions — the key is timing. Onions are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

Does the planting date change across Mississippi?

the northern hill country near Tupelo (zone 7b) runs roughly 1-2 weeks behind the state average; the Gulf Coast around Gulfport (zone 9a) can plant 1-2 weeks earlier.

What else can I plant in Mississippi around the same time?

The same early window suits peas, lettuce, spinach, and onion sets.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.