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When to Plant Celery in St. John the Baptist Parish, LA

St. John the Baptist Parish, Louisiana Zone 9b May

This month in St. John the Baptist Parish, Louisiana

A quick May briefing for St. John the Baptist Parish, Louisiana gardeners — what's urgent, what's next, and what can wait.

Avg. last frost February 20
Avg. first frost December 1
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. It's harvest week for celery

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

Coming up in June — start thinking about
  • First harvests: celery

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Celery is a marshland plant that requires consistent moisture and cool temperatures to produce crisp, flavorful stalks. It is a rewarding but demanding garden crop.

St. John the Baptist Parish, Louisiana is in USDA Zone 9b. The average last spring frost is February 20 and the first fall frost is December 1, giving you a growing season of approximately 284 days.

At an elevation of 309 feet, St. John the Baptist Parish receives approximately 53.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103°F, so Celery may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Celery will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Celery root diseases.

St. John the Baptist Parish, LA (Zone 9b) Year-round
284 days
Last Spring Frost February 20
284 growing days
First Fall Frost December 1
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St. John the Baptist 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 (148 days to spare)
Start indoors: Jan 9 Transplant: Feb 6 🍅 Harvest: May 1 – Jun 26
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Jan 23 Transplant: Feb 20 🍅 Harvest: May 15 – Jul 10
Safe Start (90%) ✓ Fits season (131 days to spare)
Start indoors: Feb 22 Transplant: Mar 22 🍅 Harvest: Jun 14 – Aug 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 St. John the Baptist Parish

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

Soil pH

Your soil pH (4.8–6.1) is more acidic than Celery prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Celery.

Organic Matter

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

How to Plant Celery

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Celery

4
successive plantings in your 284-day season

Sow every 9.1 weeks. Last sowing by Aug 03 to harvest before frost.

For a dedicated fall crop, sow by Oct 06.

Plant Water Budget

Plant needs
1.3″/week
Rainfall provides
0.8″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 361 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Celery

Celery needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.

Month Celery Needs Rainfall You Supplement Action
Jan 4" 0" ❄️ Dormant
Feb 5.6" 4" 1.6" 💧 Light watering
Mar 5.6" 4.6" 1" 💧 Light watering
Apr 5.6" 4" 1.6" 💧 Light watering
May 5.6" 4.7" 0.9" 💧 Light watering
Jun 5.6" 5" 0.6" 💧 Light watering
Jul 5.6" 6.3" 0" ✅ Rainfall sufficient
Aug 5.6" 4.7" 0.9" 💧 Light watering
Sep 5.6" 4.3" 1.3" 💧 Light watering
Oct 5.6" 3.7" 1.9" 💧 Light watering
Nov 5.6" 3.5" 2.1" 💧 Light watering
Dec 5.6" 4.8" 0.8" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in St. John the Baptist Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Celery 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.

Celery needs ~2,725 GDD — county provides 7,766 GDD Excellent fit

Celery Planting Timeline — St. John the Baptist Parish, LA

Celery Planting Calendar

Activity When Date Range
Start Indoors January 23 Jan 23 – Feb 6
Transplant Outdoors February 20 Feb 20 – Mar 6
Direct Sow January 30 Jan 30 – Feb 20
Harvest May 15 May 15 – Jul 10
Fall Sowing October 6 Oct 6 – Oct 20

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.3"/week · Only during dry spells

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

284 days in St. John the Baptist Parish

Growing Tips for Celery in St. John the Baptist Parish

Direct sow Celery outdoors after February 20 in St. John the Baptist Parish when soil has warmed and frost danger has passed.

Sandy soil in St. John the Baptist Parish dries quickly — mulch Celery with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 103°F in St. John the Baptist Parish, provide afternoon shade for Celery and water deeply in the morning.

Common pests for Celery in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Keep soil consistently moist and never let it dry out. Blanch stalks by mounding soil or using collars for milder flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celery in St. John the Baptist Parish, LA?

St. John the Baptist Parish is in Zone 9b with an average last frost of February 20. Plan your Celery planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. John the Baptist Parish, LA?

St. John the Baptist Parish, Louisiana is in USDA Hardiness Zone 9b. The average last spring frost is February 20 and first fall frost is December 1.

🌱

Your St. John the Baptist Parish Garden Planner — Free

A 24-page printable planner built for St. John the Baptist Parish (Zone 9b). 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 St. John the Baptist 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.