When to Plant Rosemary in Karnes County, TX
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.
Karnes County, Texas is in USDA Zone 8b. The average last spring frost is February 26 and the first fall frost is November 30, giving you a growing season of approximately 277 days.
At an elevation of 4,532 feet, Karnes County receives approximately 67.2 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.
Karnes County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.8
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 Karnes County
How your county's soil matches Rosemary's growing requirements.
Soil pH
Your soil pH (6.3–7.8) overlaps with Rosemary's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Karnes County is excellent for Rosemary — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Rosemary.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Rosemary.
How to Plant Rosemary
Succession Planting Rosemary
Sow every 9.1 weeks. Last sowing by Jun 03 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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 1.3" | 2.6" | 0" | ✅ Rainfall sufficient |
| Mar | 1.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Apr | 1.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 8.6" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 11.7" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 9.1" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 8.7" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Nov | 1.3" | 2" | 0" | ✅ Rainfall sufficient |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Karnes County). 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 — Karnes County, TX
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 5 | Mar 5 – Mar 19 |
| Harvest | May 28 | May 28 – Oct 15 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | Harvest |
| 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: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
277 days in Karnes County
Growing Tips for Rosemary in Karnes County
Direct sow Rosemary outdoors after February 26 in Karnes County when soil has warmed and frost danger has passed.
With 67" of annual rainfall in Karnes County, ensure good drainage for Rosemary — excess moisture can promote root rot and fungal diseases.
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 Karnes County, TX?
Karnes County is in Zone 8b with an average last frost of February 26. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Karnes County, TX?
Karnes County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is February 26 and first fall frost is November 30.
Plan Your Garden with Confidence
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