When to Plant Rue in St. Mary's County, MD
Rue is a bitter, aromatic perennial herb with bluish-green foliage used historically in medicine and as a pest deterrent. Handle with care as its sap can cause skin irritation.
St. Mary's County, Maryland is in USDA Zone 7a. The average last spring frost is April 5 and the first fall frost is November 4, giving you a growing season of approximately 213 days.
At an elevation of 156 feet, St. Mary's County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Rue during the growing season.
St. Mary's County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.9
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 St. Mary's County
How your county's soil matches Rue's growing requirements.
Soil pH
Your soil pH (5.5–6.9) overlaps with Rue's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in St. Mary's County is excellent for Rue — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Rue.
How to Plant Rue
Succession Planting Rue
Sow every 8 weeks. Last sowing by Aug 06 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Rue
Rue needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Rue Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.1" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | — | 3.3" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.7" | 0" | ✅ Rainfall sufficient |
| Dec | — | 2.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in St. Mary's County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rue 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.
Rue Planting Timeline — St. Mary's County, MD
Rue Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 12 | Apr 12 – Apr 26 |
| Harvest | June 21 | Jun 21 – Aug 23 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
213 days in St. Mary's County
Growing Tips for Rue in St. Mary's County
Direct sow Rue outdoors after April 05 in St. Mary's County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors or direct sow. Plant in well-drained soil. Wear gloves when handling as sap can cause phytophotodermatitis. Prune in early spring.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Rue in Other Locations
Frequently Asked Questions
When should I plant Rue in St. Mary's County, MD?
St. Mary's County is in Zone 7a with an average last frost of April 5. Plan your Rue planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Mary's County, MD?
St. Mary's County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is April 5 and first fall frost is November 4.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help St. Mary's County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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