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When to plant Tarragon in Johnson County, MO

Johnson County's short 193-day growing season means one Tarragon planting between April 20 and May 4. No fall crop in Zone 6b.

When to Plant Tarragon in Johnson County, MO

Johnson County, Missouri Zone 6b June

Your June planting checklist for Johnson County, Missouri

Each item below is timed to Johnson County, Missouri's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 13
Avg. first frost October 23
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
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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.

Johnson County, Missouri is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 23, giving you a growing season of approximately 193 days.

At an elevation of 1,218 feet, Johnson County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Tarragon during the growing season.

Johnson County, MO (Zone 6b) Moderate season
193 days
Last Spring Frost April 13
193 growing days
First Fall Frost October 23

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Tarragon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (54 days to spare)
Transplant: Apr 12 🍅 Harvest: Jun 14 – Aug 23
Recommended (50%) ✓ Fits season (53 days to spare)
Transplant: Apr 20 🍅 Harvest: Jun 22 – Aug 31
Safe Start (90%) ✓ Fits season (54 days to spare)
Transplant: May 2 🍅 Harvest: Jul 4 – Sep 12

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 Johnson County

How your county's soil matches Tarragon's growing requirements.

Soil pH

Your soil pH (5.3–6.5) is more acidic than Tarragon prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Johnson County is excellent for Tarragon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Tarragon.

How to Plant Tarragon

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Tarragon

3
successive plantings in your 193-day season

Sow every 6.9 weeks. Last sowing by Jul 25 to harvest before frost.

Tarragon Water Budget

Plant needs
0.4″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 1.7" 3.6" 0" ✅ Rainfall sufficient
May 1.7" 4.5" 0" ✅ Rainfall sufficient
Jun 1.7" 5.8" 0" ✅ Rainfall sufficient
Jul 1.7" 4.1" 0" ✅ Rainfall sufficient
Aug 1.7" 4.9" 0" ✅ Rainfall sufficient
Sep 1.7" 3.8" 0" ✅ Rainfall sufficient
Oct 1.7" 3" 0" ✅ Rainfall sufficient
Nov 2.8" 0" ❄️ Dormant
Dec 2.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson 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 needs ~1,088 GDD — county provides 2,798 GDD Excellent fit

Tarragon Planting Timeline — Johnson County, MO

Tarragon Planting Calendar

Activity When Date Range
Transplant Outdoors April 20 Apr 20 – May 4
Harvest June 22 Jun 22 – Aug 31

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
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 6b

📆 Growing Season

193 days in Johnson County

Growing Tips for Tarragon in Johnson County

Direct sow Tarragon outdoors after April 13 in Johnson 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 →

Frequently Asked Questions

When should I plant Tarragon in Johnson County, MO?

Johnson County is in Zone 6b with an average last frost of April 13. Plan your Tarragon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, MO?

Johnson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 23.

When should I plant Tarragon in Johnson County, MO?

In Johnson County, MO, plant Tarragon after the last frost (around April 13) and before the first frost (around October 23). Best results when soil holds above 50°F.

What growing zone is Johnson County, MO for Tarragon?

Johnson 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 Johnson County's climate?

Yes — Tarragon grows well in Johnson County's temperate climate. Johnson County averages a 193-day frost-free season, with last frost around April 13 and first frost around October 23.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Johnson County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.