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When to Plant Lavender in St. Bernard Parish, LA

St. Bernard Parish, Louisiana Zone 9b May

May to-do list for St. Bernard Parish, Louisiana

Each item below is timed to St. Bernard Parish, Louisiana's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost February 2
Avg. first frost December 11
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. It's harvest week for lavender

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

Get ahead of June
  • First harvests: lavender

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Lavender is a fragrant perennial herb with silvery foliage and purple flower spikes. It is prized for its essential oils, culinary uses, and ornamental beauty.

St. Bernard Parish, Louisiana is in USDA Zone 9b. The average last spring frost is February 2 and the first fall frost is December 11, giving you a growing season of approximately 312 days.

At an elevation of 455 feet, St. Bernard Parish receives approximately 51.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 104°F, so Lavender may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Lavender will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Lavender root diseases.

St. Bernard Parish, LA (Zone 9b) Year-round
312 days
Last Spring Frost February 2
312 growing days
First Fall Frost December 11
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St. Bernard Parish Soil Profile

Soil Type

Sandy Loam

Soil pH

5.2-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (66 days to spare)
Transplant: Jan 29 🍅 Harvest: Apr 30 – Oct 1
Recommended (50%) ✓ Fits season (60 days to spare)
Transplant: Feb 9 🍅 Harvest: May 11 – Oct 12
Safe Start (90%) ✓ Fits season (43 days to spare)
Transplant: Mar 12 🍅 Harvest: Jun 11 – Nov 12

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. Bernard Parish

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

Soil pH

Your soil pH (5.2–6.5) is more acidic than Lavender prefers (6.5–8.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Lavender prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is moderate (2.0%). Annual compost additions will help Lavender.

How to Plant Lavender

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

Plant Water Budget

Plant needs
0.3″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Lavender

Lavender needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Lavender Needs Rainfall You Supplement Action
Jan 4.6" 0" ❄️ Dormant
Feb 1.3" 4.4" 0" ✅ Rainfall sufficient
Mar 1.3" 5.3" 0" ✅ Rainfall sufficient
Apr 1.3" 4" 0" ✅ Rainfall sufficient
May 1.3" 4.4" 0" ✅ Rainfall sufficient
Jun 1.3" 4.8" 0" ✅ Rainfall sufficient
Jul 1.3" 5.9" 0" ✅ Rainfall sufficient
Aug 1.3" 4.2" 0" ✅ Rainfall sufficient
Sep 1.3" 3.6" 0" ✅ Rainfall sufficient
Oct 1.3" 3.1" 0" ✅ Rainfall sufficient
Nov 1.3" 3.9" 0" ✅ Rainfall sufficient
Dec 1.3" 3.5" 0" ✅ Rainfall sufficient

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

Lavender 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.

Lavender needs ~4,060 GDD — county provides 8,764 GDD Excellent fit

Lavender Planting Timeline — St. Bernard Parish, LA

Lavender Planting Calendar

Activity When Date Range
Transplant Outdoors February 9 Feb 9 – Feb 23
Harvest May 11 May 11 – Oct 12

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

90–200 days

🧪 Soil pH

Needs 6.5–8 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

312 days in St. Bernard Parish

Growing Tips for Lavender in St. Bernard Parish

Direct sow Lavender outdoors after February 02 in St. Bernard Parish when soil has warmed and frost danger has passed.

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

With summer highs reaching 104°F in St. Bernard Parish, provide afternoon shade for Lavender and water deeply in the morning.

General growing tips

Plant in well-drained, sandy soil. Avoid heavy mulching around the crown. Prune after flowering but do not cut into old wood. Lavender resents wet winter conditions.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Lavender in St. Bernard Parish, LA?

St. Bernard Parish is in Zone 9b with an average last frost of February 2. Plan your Lavender planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Bernard Parish, LA?

St. Bernard Parish, Louisiana is in USDA Hardiness Zone 9b. The average last spring frost is February 2 and first fall frost is December 11.

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Your St. Bernard Parish Garden Planner — Free

A 24-page printable planner built for St. Bernard 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. Bernard 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.