When to Plant Tarragon in Washington County, AL
French tarragon is a perennial herb with slender leaves and a distinctive anise-like flavor essential in French cooking. It does not produce viable seed and must be propagated vegetatively.
Washington County, Alabama is in USDA Zone 8a. The average last spring frost is March 12 and the first fall frost is November 13, giving you a growing season of approximately 246 days.
At an elevation of 419 feet, Washington County receives approximately 54.8 inches of rainfall annually with predominantly clay loam soil. Summer highs average 97°F, so Tarragon may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Tarragon, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Tarragon root diseases.
Washington County Soil Profile
Soil Type
Clay Loam
Soil pH
5.3-6.6
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 Washington County
How your county's soil matches Tarragon's growing requirements.
Soil pH
Your soil pH (5.3–6.6) is more acidic than Tarragon prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Washington County is excellent for Tarragon — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Tarragon.
How to Plant Tarragon
Succession Planting Tarragon
Sow every 6.9 weeks. Last sowing by Aug 15 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Tarragon
Tarragon needs approximately 0.4 inches of water per week (1.7" per month). Here's how your county's rainfall compares month by month.
| Month | Tarragon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.3" | 0" | ❄️ Dormant |
| Feb | — | 5.1" | 0" | ❄️ Dormant |
| Mar | 1.7" | 5.4" | 0" | ✅ Rainfall sufficient |
| Apr | 1.7" | 3.7" | 0" | ✅ Rainfall sufficient |
| May | 1.7" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jun | 1.7" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 1.7" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 1.7" | 5.4" | 0" | ✅ Rainfall sufficient |
| Sep | 1.7" | 3.6" | 0" | ✅ Rainfall sufficient |
| Oct | 1.7" | 3" | 0" | ✅ Rainfall sufficient |
| Nov | 1.7" | 4.8" | 0" | ✅ Rainfall sufficient |
| Dec | — | 5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Tarragon 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.
Tarragon Planting Timeline — Washington County, AL
Tarragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 19 | Mar 19 – Apr 2 |
| Harvest | May 21 | May 21 – Jul 30 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | Transplant Outdoors |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.4"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8a
📆 Growing Season
246 days in Washington County
Growing Tips for Tarragon in Washington County
Direct sow Tarragon outdoors after March 12 in Washington County when soil has warmed and frost danger has passed.
With Washington County's clay soil (34% clay), work in 3-4 inches of compost before planting Tarragon. Avoid tilling when soil is wet to prevent compaction.
With summer highs reaching 97°F in Washington County, provide afternoon shade for Tarragon and water deeply in the morning.
Common pests for Tarragon in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Purchase plants or divisions as French tarragon does not grow true from seed. Plant in well-drained soil. Divide every 3-4 years to maintain vigor. Harvest tips regularly for best flavor.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Tarragon in Other Locations
Frequently Asked Questions
When should I plant Tarragon in Washington County, AL?
Washington County is in Zone 8a with an average last frost of March 12. Plan your Tarragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, AL?
Washington County, Alabama is in USDA Hardiness Zone 8a. The average last spring frost is March 12 and first fall frost is November 13.
Plan Your Garden with Confidence
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