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When to Plant Corn in St. Tammany Parish, LA

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

St. Tammany Parish, Louisiana is in USDA Zone 8b. The average last spring frost is February 20 and the first fall frost is November 23, giving you a growing season of approximately 276 days.

At an elevation of 321 feet, St. Tammany Parish receives approximately 57.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96ยฐF, so Corn may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Corn root diseases.

St. Tammany Parish, LA (Zone 8b) Year-round
276 days
Last Spring Frost February 20
276 growing days
First Fall Frost November 23

St. Tammany Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.8-6.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (170 days to spare)
Transplant: Jan 30 🍅 Harvest: Apr 3 – May 29
Recommended (50%) ✓ Fits season (157 days to spare)
Transplant: Feb 20 🍅 Harvest: Apr 24 – Jun 19
Safe Start (90%) ✓ Fits season (144 days to spare)
Transplant: Mar 30 🍅 Harvest: Jun 1 – Jul 27

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 St. Tammany Parish

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

Soil pH

Your soil pH (4.8โ€“6.1) is more acidic than Corn prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Corn.

Organic Matter

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

How to Plant Corn

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

Succession Planting Corn

5
successive plantings in your 276-day season

Sow every 6.9 weeks. Last sowing by Aug 15 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 424 gal / 100 sq ft

Monthly Watering Guide for Corn

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 Corn Needs Rainfall You Supplement Action
Jan โ€” 4.5" 0" โ„๏ธ Dormant
Feb 6.5" 4.5" 2" ๐Ÿ’ง Light watering
Mar 6.5" 5.8" 0.7" ๐Ÿ’ง Light watering
Apr 6.5" 4.2" 2.3" ๐Ÿ’ง Light watering
May 6.5" 5.2" 1.3" ๐Ÿ’ง Light watering
Jun 6.5" 4.6" 1.9" ๐Ÿ’ง Light watering
Jul 6.5" 6.8" 0" โœ… Rainfall sufficient
Aug 6.5" 5.3" 1.2" ๐Ÿ’ง Light watering
Sep 6.5" 4.2" 2.3" ๐Ÿ’ง Light watering
Oct 6.5" 4.1" 2.4" ๐Ÿ’ง Light watering
Nov 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
Dec โ€” 4.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Febโ€“Nov in St. Tammany Parish). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

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" โ€” every day above 50ยฐF 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.

Corn needs ~1,760 GDD — county provides 6,094 GDD Excellent fit

Corn Planting Timeline โ€” St. Tammany Parish, LA

Corn Planting Calendar

Activity When Date Range
Direct Sow February 27 Feb 27 โ€“ Mar 20
Harvest May 1 May 1 โ€“ Jun 26

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Direct Sow
March Direct Sow
April โ€”
May Harvest
June Harvest
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

276 days in St. Tammany Parish

Growing Tips for Corn in St. Tammany Parish

Direct sow Corn outdoors after February 20 in St. Tammany Parish when soil has warmed and frost danger has passed.

Sandy soil in St. Tammany Parish dries quickly โ€” mulch Corn with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96ยฐF in St. Tammany Parish, provide afternoon shade for Corn and water deeply in the morning.

Common pests for 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 rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Recommended Corn Varieties for St. Tammany Parish

Heat-tolerant varieties that silk well in high temps

Silver Queen (92d) Incredible (85d)

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in St. Tammany Parish, LA?

St. Tammany Parish is in Zone 8b with an average last frost of February 20. Plan your Corn planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. Tammany Parish, LA?

St. Tammany Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is February 20 and first fall frost is November 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help St. Tammany Parish gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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