When to Plant Rosemary in LaSalle Parish, LA
April to-do list for LaSalle Parish, Louisiana
If you only do a handful of things in the garden this April, make it these. They're sequenced around your zone's frost timing.
Rosemary is an aromatic evergreen shrub with needle-like leaves and a piney, citrus flavor. It is a Mediterranean herb that thrives in warm, dry conditions.
LaSalle Parish, Louisiana is in USDA Zone 8b. The average last spring frost is March 2 and the first fall frost is November 19, giving you a growing season of approximately 262 days.
At an elevation of 262 feet, LaSalle Parish receives approximately 52.2 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Rosemary may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rosemary root diseases.
LaSalle Parish Soil Profile
Soil Type
Loam
Soil pH
6.2-7.2
Drainage
Well Drained
Plant Planting Risk Windows
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 LaSalle Parish
How your county's soil matches Rosemary's growing requirements.
Soil pH
Your soil pH (6.2–7.2) is within Rosemary's preferred range (6.0–7.5).
Soil Texture
The loam soil in LaSalle Parish is excellent for Rosemary — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Rosemary.
How to Plant Rosemary
Succession Planting Rosemary
Sow every 9.1 weeks. Last sowing by May 23 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Rosemary
Rosemary 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 | Rosemary Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.6" | 0" | ❄️ Dormant |
| Feb | — | 4.3" | 0" | ❄️ Dormant |
| Mar | 1.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Apr | 1.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 4" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 5.8" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | 1.3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in LaSalle Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rosemary 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.
Rosemary Planting Timeline — LaSalle Parish, LA
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 9 | Mar 9 – Mar 23 |
| Harvest | June 1 | Jun 1 – Oct 19 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
80–180 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 8b
📆 Growing Season
262 days in LaSalle Parish
Growing Tips for Rosemary in LaSalle Parish
Direct sow Rosemary outdoors after March 02 in LaSalle Parish when soil has warmed and frost danger has passed.
General growing tips
Grow in well-drained soil and avoid overwatering. In cold climates, grow in containers and bring indoors for winter. Propagate from stem cuttings for faster results than seed.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in LaSalle Parish, LA?
LaSalle Parish is in Zone 8b with an average last frost of March 2. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is LaSalle Parish, LA?
LaSalle Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is March 2 and first fall frost is November 19.
Your LaSalle Parish Garden Planner — Free
A 24-page printable planner built for LaSalle Parish (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.