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When to Plant Tomatoes in Concordia Parish, LA

Concordia Parish, Louisiana Zone 9a May

Your May gardening checklist

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 8
Avg. first frost November 15
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.6 hrs
  1. It's harvest week for tomatoes

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Before June arrives, get these ready
  • First harvests: tomatoes

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Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.

Concordia Parish, Louisiana is in USDA Zone 9a. The average last spring frost is March 8 and the first fall frost is November 15, giving you a growing season of approximately 252 days.

At an elevation of 377 feet, Concordia Parish receives approximately 60.5 inches of rainfall annually with predominantly loam soil. Summer highs average 92°F, providing good warmth for Tomatoes during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tomatoes root diseases.

Concordia Parish, LA (Zone 9a) Long season
252 days
Last Spring Frost March 8
252 growing days
First Fall Frost November 15

Concordia Parish Soil Profile

Soil Type

Loam

Soil pH

6-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (109 days to spare)
Start indoors: Jan 18 Transplant: Mar 8 🍅 Harvest: May 10 – Jul 19
Recommended (50%) ✓ Fits season (112 days to spare)
Start indoors: Jan 25 Transplant: Mar 15 🍅 Harvest: May 17 – Jul 26
Safe Start (90%) ✓ Fits season (111 days to spare)
Start indoors: Feb 12 Transplant: Apr 2 🍅 Harvest: Jun 4 – Aug 13

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 Concordia Parish

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

Soil pH

Your soil pH (6.0–7.3) overlaps with Tomatoes's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Concordia Parish is excellent for Tomatoes — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Tomatoes.

How to Plant Tomatoes

0.5"
Planting Depth
24"
Between Plants
36"
Between Rows

Succession Planting Tomatoes

5
successive plantings in your 252-day season

Sow every 6.9 weeks. Last sowing by Aug 22 to harvest before frost.

Plant Water Budget

Plant needs
1.2″/week
Rainfall provides
1.0″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 430 gal / 100 sq ft

Monthly Watering Guide for Tomatoes

Tomatoes needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.

Month Tomatoes Needs Rainfall You Supplement Action
Jan 5.1" 0" ❄️ Dormant
Feb 5.6" 0" ❄️ Dormant
Mar 5.2" 5.9" 0" ✅ Rainfall sufficient
Apr 5.2" 5.1" 0.1" 💧 Light watering
May 5.2" 5.2" 0" ✅ Rainfall sufficient
Jun 5.2" 4.7" 0.5" 💧 Light watering
Jul 5.2" 5.8" 0" ✅ Rainfall sufficient
Aug 5.2" 6.1" 0" ✅ Rainfall sufficient
Sep 5.2" 4.4" 0.8" 💧 Light watering
Oct 5.2" 3.4" 1.8" 💧 Light watering
Nov 5.2" 5" 0.2" 💧 Light watering
Dec 4.2" 0" ❄️ Dormant

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

Tomatoes 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.

Tomatoes needs ~1,378 GDD — county provides 4,788 GDD Excellent fit

Tomatoes Planting Timeline — Concordia Parish, LA

Tomatoes Planting Calendar

Activity When Date Range
Start Indoors January 25 Jan 25 – Feb 8
Transplant Outdoors March 15 Mar 15 – Mar 29
Direct Sow March 8 Mar 8 – Mar 29
Harvest May 17 May 17 – Jul 26

Plant 0.5" deep · 24" apart · Rows 36" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors Direct Sow
April
May Harvest
June Harvest
July Harvest
August
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.2"/week · Only during dry spells

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

252 days in Concordia Parish

Growing Tips for Tomatoes in Concordia Parish

Direct sow Tomatoes outdoors after March 08 in Concordia Parish when soil has warmed and frost danger has passed.

Common pests for Tomatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.

Recommended Tomatoes Varieties for Concordia Parish

Your long season supports large indeterminate heirloom types

Brandywine (80d) Cherokee Purple (80d) San Marzano (80d) Mortgage Lifter (85d)

Disease-resistant varieties for your humid climate

Mountain Merit (VF) Defiant (LB) Iron Lady (EB/LB/SF)

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Fennel
  • Potatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Tomatoes Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Scoop seeds from ripe fruit; ferment 2-3 days to remove gel coating.
Storage Store airtight; viable 4-6 years at 35°F, under 45% humidity.

Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.

Frequently Asked Questions

When should I plant Tomatoes in Concordia Parish, LA?

Concordia Parish is in Zone 9a with an average last frost of March 8. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.

What planting zone is Concordia Parish, LA?

Concordia Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 8 and first fall frost is November 15.

🌱

Your Concordia Parish Garden Planner — Free

A 24-page printable planner built for Concordia 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.

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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 Concordia 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.