When to Plant Rosemary in Williamson 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.
Williamson County, Texas is in USDA Zone 8b. The average last spring frost is March 5 and the first fall frost is November 22, giving you a growing season of approximately 262 days.
At an elevation of 1,023 feet, Williamson County receives approximately 53.3 inches of rainfall annually with predominantly clay soil. Summer highs average 94°F, providing good warmth for Rosemary during the growing season. Clay soil retains moisture well for Rosemary, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rosemary root diseases.
Williamson County Soil Profile
Soil Type
Clay
Soil pH
7.1-7.8
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 Williamson County
How your county's soil matches Rosemary's growing requirements.
Soil pH
Your soil pH (7.1–7.8) overlaps with Rosemary's range (6.0–7.5), though not a perfect match.
Soil Texture
Heavy clay soil (46% clay) in Williamson County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.
Drainage
Rosemary prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Rosemary.
How to Plant Rosemary
Succession Planting Rosemary
Sow every 9.1 weeks. Last sowing by May 26 to harvest before frost.
Plant Water Budget
Rosemary Planting Timeline — Williamson County, TX
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 12 | Mar 12 – Mar 26 |
| Harvest | June 4 | Jun 4 – Oct 22 |
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: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
262 days in Williamson County
Growing Tips for Rosemary in Williamson County
Direct sow Rosemary outdoors after March 05 in Williamson County when soil has warmed and frost danger has passed.
With Williamson County's clay soil (46% clay), work in 3-4 inches of compost before planting Rosemary. Avoid tilling when soil is wet to prevent compaction.
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
Level Up Your Garden
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in Williamson County, TX?
Williamson County is in Zone 8b with an average last frost of March 5. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Williamson County, TX?
Williamson County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 5 and first fall frost is November 22.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Williamson County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.
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