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When to Plant Lemongrass in St. Charles Parish, LA

St. Charles Parish, Louisiana Zone 9a April

April to-do list for St. Charles Parish, Louisiana

A quick April briefing for St. Charles 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") 68°F
Watering Low
Pest pressure High
Daylight 12.7 hrs
  1. Begin indoor sowing: lemongrass

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

A few tasks this April that'll pay off in May
  • First harvests: lemongrass

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Lemongrass is a tropical grass with a strong citrus aroma used extensively in Southeast Asian cuisine. The swollen stem bases are the most flavorful part.

St. Charles Parish, Louisiana is in USDA Zone 9a. 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 154 feet, St. Charles Parish receives approximately 54.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103°F, so Lemongrass may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Lemongrass will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lemongrass root diseases.

St. Charles Parish, LA (Zone 9a) Year-round
284 days
Last Spring Frost February 20
284 growing days
First Fall Frost December 1

St. Charles Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

4.9-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (113 days to spare)
Start indoors: Dec 26 Transplant: Feb 13 🍅 Harvest: May 1 – Jul 31
Recommended (50%) ✓ Fits season (109 days to spare)
Start indoors: Jan 9 Transplant: Feb 27 🍅 Harvest: May 15 – Aug 14
Safe Start (90%) ✓ Fits season (96 days to spare)
Start indoors: Feb 8 Transplant: Mar 29 🍅 Harvest: Jun 14 – Sep 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 St. Charles Parish

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

Soil pH

Your soil pH (4.9–6.3) overlaps with Lemongrass's range (5.5–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Lemongrass.

Organic Matter

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

How to Plant Lemongrass

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Lemongrass

4
successive plantings in your 284-day season

Sow every 8.6 weeks. Last sowing by Aug 03 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 634 gal / 100 sq ft

Monthly Watering Guide for Lemongrass

Lemongrass 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 Lemongrass Needs Rainfall You Supplement Action
Jan 4.3" 0" ❄️ Dormant
Feb 6.5" 4.8" 1.7" 💧 Light watering
Mar 6.5" 4.9" 1.6" 💧 Light watering
Apr 6.5" 4.2" 2.3" 💧 Light watering
May 6.5" 4.8" 1.7" 💧 Light watering
Jun 6.5" 4.6" 1.9" 💧 Light watering
Jul 6.5" 5.9" 0.6" 💧 Light watering
Aug 6.5" 5" 1.5" 💧 Light watering
Sep 6.5" 4.5" 2" 💧 Light watering
Oct 6.5" 3" 3.5" 🚿 Regular watering
Nov 6.5" 4.3" 2.2" 💧 Light watering
Dec 6.5" 4" 2.5" 💧 Light watering

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

Lemongrass 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.

Lemongrass needs ~2,657 GDD — county provides 7,766 GDD Excellent fit

Lemongrass Planting Timeline — St. Charles Parish, LA

Lemongrass Planting Calendar

Activity When Date Range
Start Indoors January 9 Jan 9 – Jan 23
Transplant Outdoors February 27 Feb 27 – Mar 13
Direct Sow February 27 Feb 27 – Mar 20
Harvest May 15 May 15 – Aug 14

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · Only during dry spells

📅 Days to Maturity

75–120 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

284 days in St. Charles Parish

Growing Tips for Lemongrass in St. Charles Parish

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

Sandy soil in St. Charles Parish dries quickly — mulch Lemongrass 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. Charles Parish, provide afternoon shade for Lemongrass and water deeply in the morning.

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

General growing tips

Start from divisions or store-bought stalks rooted in water. Grow in rich, moist soil with full sun. In cold climates, grow in containers and overwinter indoors.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lemongrass in St. Charles Parish, LA?

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

What planting zone is St. Charles Parish, LA?

St. Charles Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is February 20 and first fall frost is December 1.

🌱

Your St. Charles Parish Garden Planner — Free

A 24-page printable planner built for St. Charles 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 St. Charles Parish, LA. Local conditions may vary. Last updated: April 2026.

Sources & credits

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