When to Plant Valerian in Charles County, MD
Valerian is a tall perennial herb with fragrant white or pink flower clusters, valued for its root which is used as a natural sleep aid. It attracts pollinators and earthworms.
Charles County, Maryland is in USDA Zone 7a. The average last spring frost is March 29 and the first fall frost is November 14, giving you a growing season of approximately 230 days.
At an elevation of 382 feet, Charles County receives approximately 38.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Valerian during the growing season.
Charles County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.8
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 Charles County
How your county's soil matches Valerian's growing requirements.
Soil pH
Your soil pH (5.7–6.8) is within Valerian's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Charles County is excellent for Valerian — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Valerian.
How to Plant Valerian
Plant Water Budget
Monthly Watering Guide for Valerian
Valerian needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Valerian Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Apr | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| May | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jun | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jul | 4.3" | 4" | 0.3" | 💧 Light watering |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Oct | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Nov | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Dec | — | 2.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Charles County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Valerian 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.
Valerian Planting Timeline — Charles County, MD
Valerian Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 5 | Apr 5 – Apr 19 |
| Harvest | August 9 | Aug 9 – Nov 15 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
120–180 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 7a
📆 Growing Season
230 days in Charles County
Growing Tips for Valerian in Charles County
Direct sow Valerian outdoors after March 29 in Charles County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors and transplant after last frost. Harvest roots in fall of the second year. Deadhead flowers unless you want self-seeding. Cats are attracted to valerian root.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Valerian in Other Locations
Frequently Asked Questions
When should I plant Valerian in Charles County, MD?
Charles County is in Zone 7a with an average last frost of March 29. Plan your Valerian planting based on this frost date — see the calendar above for exact timing.
What planting zone is Charles County, MD?
Charles County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is March 29 and first fall frost is November 14.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Charles County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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