Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 70740 — Grosse Tete, LA

ZIP code 70740 (Grosse Tete, Iberville County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is February 28 and the first fall frost November 24.

Where ZIP 70740 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone9a20 to 25 °F

Coldest night−6.7 to −3.9 °C

Last frostFeb 28

First frostNov 24

2012 zone9a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Grosse Tete, LA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Grosse Tete, LA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostFebruary 28median — 50% chance of a later frost

Safe for tender plantsMarch 21only 10% chance of frost after

First fall frostNovember 24median — 10% chance by Nov 6

Growing season268 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 8 and returns around December 9.

From the NOAA station Brusly 2 W, LA — 11 miles away, elevation 20 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 70740

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Jan 17 – Jan 31

SpinachSow outdoors · Jan 17 – Feb 7

Broccoli, cabbageStart indoors · Dec 20 – Jan 3

Broccoli, cabbageTransplant · Feb 7 – Feb 21

Onion setsPlant outdoors · Jan 31 – Feb 14

PotatoesPlant outdoors · Feb 7 – Feb 21

LettuceSow outdoors · Jan 31 – Feb 14

Carrots, beetsSow outdoors · Feb 7 – Feb 21

TomatoesStart indoors · Jan 3 – Jan 17

TomatoesTransplant · Mar 7 – Mar 21

Peppers, eggplantStart indoors · Dec 20 – Jan 3

Peppers, eggplantTransplant · Mar 14 – Mar 28

BeansSow outdoors · Mar 7 – Mar 21

Sweet cornSow outdoors · Mar 7 – Mar 21

Cucumbers, squashSow outdoors · Mar 7 – Mar 21

Fall lettuce, spinachSow outdoors · Sep 29 – Oct 13

GarlicPlant cloves · Nov 10 – Dec 15

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Feb 28) and first fall frost (Nov 24) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 70740 came on Jan 11 — 14 days earlier than the 1991–2020 average (Jan 25).

average
Jan 252026
Jan 11

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 9a in Louisiana

517 plants native to the lower 48 states, recorded in Louisiana, and rated by the USDA to survive 20 °F or colder — the bottom of zone 9a. Each links to its USDA PLANTS profile.

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Grosse Tete, LA.

Soil in Grosse Tete, LA

The soil mapped at the center of ZIP 70740 is Tunica — clay, poorly drained.

TextureClayholds water and nutrients; slow to drain and warm up

pH6.7neutral; most vegetables like 6.0–7.0

DrainagePoorly drainedconsider raised beds

Organic matter2%moderate

Hydrologic groupDwater soaks in very slowly

Farmland classprime farmlandUSDA classification

Map unit: Tunica clay.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 70740; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Grosse Tete, LA

Summer high92 °Faverage high, August

Winter low40 °Faverage low, January

Hot days85days a year at 90 °F or more

Freezing nights26nights a year at 32 °F or less

Growing degree days6,634base 50 °F — the season’s usable heat

Longest day14 h 06 mindaylight on June 21

Shortest day10 h 11 mindaylight on December 21

Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb

Precipitation61.4 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Brusly 2 W, LA (11 mi away); precipitation: Plaquemine 2 N, LA (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 9a.

707579a

Maringouin, LA · 7 mi

Plaquemine, LA · 10 mi

707109a

Addis, LA · 10 mi

707659a

Plaquemine, LA · 12 mi

707679a

Port Allen, LA · 13 mi

708209a

Baton Rouge, LA · 14 mi

Louisiana planting zones →

Questions about 70740

What planting zone is ZIP code 70740?

ZIP code 70740 (Grosse Tete, LA) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in Grosse Tete, LA?

The median last spring frost (32 °F) near 70740 is February 28; after March 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Brusly 2 W station.

When is the first frost in Grosse Tete, LA?

The median first fall frost near 70740 is November 24, giving a median frost-free growing season of 268 days.

When should I plant tomatoes in 70740?

Start tomato seeds indoors around Jan 3 – Jan 17 and set transplants outside around Mar 7 – Mar 21, one to three weeks after the median last frost.

How much rain and snow does 70740 get?

About 61.4 inches of precipitation a year (NOAA 1991–2020 normals, Plaquemine 2 N station).

How hot do summers get in Grosse Tete, LA?

The average high peaks at 92 °F in August, with about 85 days a year at 90 °F or more.

What kind of soil does 70740 have?

The USDA soil survey maps Tunica at the center of ZIP 70740: clay, poorly drained, pH about 6.7 (neutral).

Did spring come early in Grosse Tete, LA in 2026?

Spring leaf-out near 70740 came on Jan 11 in 2026, 14 days earlier than the 1991–2020 average (Jan 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Grosse Tete, LA?

Short-day onions: the longest day near 70740 is 14 h 06 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.