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When to Plant Tarragon in Ottawa County, OK

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.

Ottawa County, Oklahoma is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 716 feet, Ottawa County receives approximately 29.5 inches of rainfall annually with predominantly loam soil. Summer highs average 93ยฐF, providing good warmth for Tarragon during the growing season.

Ottawa County, OK (Zone 7a) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Ottawa County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (59 days to spare)
Transplant: Apr 10 🍅 Harvest: Jun 12 – Aug 21
Recommended (50%) ✓ Fits season (60 days to spare)
Transplant: Apr 16 🍅 Harvest: Jun 18 – Aug 27
Safe Start (90%) ✓ Fits season (60 days to spare)
Transplant: Apr 30 🍅 Harvest: Jul 2 – Sep 10

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 Ottawa County

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

Soil pH

Your soil pH (6.8โ€“7.8) overlaps with Tarragon's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Ottawa County is excellent for Tarragon โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) โ€” Tarragon will thrive.

How to Plant Tarragon

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

Succession Planting Tarragon

3
successive plantings in your 200-day season

Sow every 6.9 weeks. Last sowing by Jul 28 to harvest before frost.

Plant Water Budget

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

Water stress score is 6/10 โ€” 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 โ€” 0.8" 0" โ„๏ธ Dormant
Feb โ€” 1" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr 1.7" 2.9" 0" โœ… Rainfall sufficient
May 1.7" 4.6" 0" โœ… Rainfall sufficient
Jun 1.7" 4.7" 0" โœ… Rainfall sufficient
Jul 1.7" 3.5" 0" โœ… Rainfall sufficient
Aug 1.7" 3.6" 0" โœ… Rainfall sufficient
Sep 1.7" 2.8" 0" โœ… Rainfall sufficient
Oct 1.7" 1.9" 0" โœ… Rainfall sufficient
Nov โ€” 0.9" 0" โ„๏ธ Dormant
Dec โ€” 0.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Ottawa County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~1,481 GDD — county provides 3,950 GDD Excellent fit

Tarragon Planting Timeline โ€” Ottawa County, OK

Tarragon Planting Calendar

Activity When Date Range
Transplant Outdoors April 16 Apr 16 โ€“ Apr 30
Harvest June 18 Jun 18 โ€“ Aug 27

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May โ€”
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.4"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

200 days in Ottawa County

Growing Tips for Tarragon in Ottawa County

Direct sow Tarragon outdoors after April 09 in Ottawa 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 Ottawa County, OK?

Ottawa County is in Zone 7a with an average last frost of April 9. Plan your Tarragon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ottawa County, OK?

Ottawa County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ottawa County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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