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When to Plant Sweet Corn in Tangipahoa Parish, LA

Tangipahoa Parish, Louisiana Zone 9a May

May in the garden — Tangipahoa Parish, Louisiana

Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 4
Avg. first frost November 23
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Collect sweet corn at their peak

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Before June arrives, get these ready
  • First harvests: sweet corn

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Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.

Tangipahoa Parish, Louisiana is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 23, giving you a growing season of approximately 264 days.

At an elevation of 111 feet, Tangipahoa Parish receives approximately 56.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Sweet Corn during the growing season. Sandy soil warms quickly in spring — great for early planting — but Sweet Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.

Tangipahoa Parish, LA (Zone 9a) Long season
264 days
Last Spring Frost March 4
264 growing days
First Fall Frost November 23
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Tangipahoa Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (166 days to spare)
Transplant: Feb 18 🍅 Harvest: Apr 22 – Jun 3
Recommended (50%) ✓ Fits season (159 days to spare)
Transplant: Mar 4 🍅 Harvest: May 6 – Jun 17
Safe Start (90%) ✓ Fits season (158 days to spare)
Transplant: Mar 26 🍅 Harvest: May 28 – Jul 9

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Tangipahoa Parish

How your county's soil matches Sweet Corn's growing requirements.

Soil pH

Your soil pH (4.8–6.0) is more acidic than Sweet Corn prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Tangipahoa Parish warms quickly in spring but drains fast. Sweet Corn will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Sweet Corn.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Sweet Corn.

How to Plant Sweet Corn

1"
Planting Depth
12"
Between Plants
36"
Between Rows

Succession Planting Sweet Corn

5
successive plantings in your 264-day season

Sow every 6.9 weeks. Last sowing by Aug 25 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 348 gal / 100 sq ft

Monthly Watering Guide for Sweet Corn

Sweet Corn needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Sweet Corn Needs Rainfall You Supplement Action
Jan 3.9" 0" ❄️ Dormant
Feb 4.9" 0" ❄️ Dormant
Mar 6.5" 4.7" 1.8" 💧 Light watering
Apr 6.5" 4.7" 1.8" 💧 Light watering
May 6.5" 5" 1.5" 💧 Light watering
Jun 6.5" 4.8" 1.7" 💧 Light watering
Jul 6.5" 6.2" 0.3" 💧 Light watering
Aug 6.5" 5.8" 0.7" 💧 Light watering
Sep 6.5" 4.3" 2.2" 💧 Light watering
Oct 6.5" 3.9" 2.6" 💧 Light watering
Nov 6.5" 4" 2.5" 💧 Light watering
Dec 4.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Tangipahoa Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sweet Corn Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sweet Corn needs ~1,538 GDD — county provides 5,412 GDD Excellent fit

Sweet Corn Planting Timeline — Tangipahoa Parish, LA

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow March 11 Mar 11 – Apr 1
Harvest May 13 May 13 – Jun 24

Plant 1" deep · 12" apart · Rows 36" apart

Month-by-Month Timeline

MonthActivities
January
February
March Direct Sow
April Direct Sow
May Harvest
June Harvest
July
August
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

264 days in Tangipahoa Parish

Growing Tips for Sweet Corn in Tangipahoa Parish

Direct sow Sweet Corn outdoors after March 04 in Tangipahoa Parish when soil has warmed and frost danger has passed.

Sandy soil in Tangipahoa Parish dries quickly — mulch Sweet Corn with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Sweet Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant in blocks of at least 4 rows for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Corn in Tangipahoa Parish, LA?

Tangipahoa Parish is in Zone 9a with an average last frost of March 4. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tangipahoa Parish, LA?

Tangipahoa Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 23.

🌱

Your Tangipahoa Parish Garden Planner — Free

A 24-page printable planner built for Tangipahoa Parish (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Tangipahoa Parish, LA. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.