When to Plant Rosemary in Caswell County, NC
May in Caswell County, North Carolina — your action list
Welcome to May in Zone 7b. These are the moves that will have the biggest impact on your growing season.
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.
Caswell County, North Carolina is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.
At an elevation of 608 feet, Caswell County receives approximately 42.7 inches of rainfall annually with predominantly clay loam 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.
Caswell County Soil Profile
Soil Type
Clay Loam
Soil pH
5.7-6.2
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 Caswell County
How your county's soil matches Rosemary's growing requirements.
Soil pH
Your soil pH (5.7–6.2) is more acidic than Rosemary prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Caswell County is excellent for Rosemary — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Rosemary.
How to Plant Rosemary
Succession Planting Rosemary
Sow every 9.1 weeks. Last sowing by May 04 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 | — | 3.9" | 0" | ❄️ Dormant |
| Feb | — | 3.8" | 0" | ❄️ Dormant |
| Mar | — | 3.9" | 0" | ❄️ Dormant |
| Apr | 1.3" | 3.2" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 3" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 4" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 2.9" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 2.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.3" | 0" | ❄️ Dormant |
| Dec | — | 3.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Caswell 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 — Caswell County, NC
Rosemary Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Harvest | July 6 | Jul 6 – Nov 23 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| 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: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
208 days in Caswell County
Growing Tips for Rosemary in Caswell County
Direct sow Rosemary outdoors after April 06 in Caswell County when soil has warmed and frost danger has passed.
With Caswell County's clay soil (34% 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
Check more plant combinations with our Companion Planting Checker →
Rosemary in Other Locations
Frequently Asked Questions
When should I plant Rosemary in Caswell County, NC?
Caswell County is in Zone 7b with an average last frost of April 6. Plan your Rosemary planting based on this frost date — see the calendar above for exact timing.
What planting zone is Caswell County, NC?
Caswell County, North Carolina is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 31.
Your Caswell County Garden Planner — Free
A 24-page printable planner built for Caswell County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.