When to plant Tarragon in Clark County, IL
Plant Tarragon in Clark County, between April 21 and May 5 — the only viable window. Zone 6b's short season (186 frost-free days) rules out a fall crop.
When to Plant Tarragon in Clark County, IL
Your June gardening checklist
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Clark County, Illinois.
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Start harvesting tarragon
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Coming up in July — start thinking about
- First harvests: tarragon
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.
Clark County, Illinois is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 17, giving you a growing season of approximately 186 days.
At an elevation of 591 feet, Clark County receives approximately 41.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Tarragon during the growing season.
Clark County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-6.8
Drainage
Well Drained
Tarragon 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 Clark County
How your county's soil matches Tarragon's growing requirements.
Soil pH
Your soil pH (6.2–6.8) is within Tarragon's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Clark County is excellent for Tarragon — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.9%) — Tarragon will thrive.
How to Plant Tarragon
Succession Planting Tarragon
Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.
Tarragon Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 1.7" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 1.7" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 1.7" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jul | 1.7" | 4.1" | 0" | ✅ Rainfall sufficient |
| Aug | 1.7" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 1.7" | 4" | 0" | ✅ Rainfall sufficient |
| Oct | 1.7" | 3.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clark 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 — Clark County, IL
Tarragon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Harvest | June 23 | Jun 23 – Sep 1 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| 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: ideal
🗺️ USDA Zone
Zone 6b
📆 Growing Season
186 days in Clark County
Growing Tips for Tarragon in Clark County
Direct sow Tarragon outdoors after April 14 in Clark County when soil has warmed and frost danger has passed.
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 Clark County, IL?
Clark County is in Zone 6b with an average last frost of April 14. Plan your Tarragon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clark County, IL?
Clark County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 17.
When should I plant Tarragon in Clark County, IL?
In Clark County, IL, plant Tarragon after the last frost (around April 14) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Clark County, IL for Tarragon?
Clark County sits in USDA Zone 6b. Tarragon grows reliably in zones 4a through 9b, so it's a good fit here.
Can Tarragon grow in Clark County's climate?
Yes — Tarragon grows well in Clark County's temperate climate. Clark County averages a 186-day frost-free season, with last frost around April 14 and first frost around October 17.
Your Clark County Garden Planner — Free
A 22-page printable planner built for Clark County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.