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When to Plant Cilantro in Jefferson County, OK

Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.

Jefferson County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 26 and the first fall frost is November 9, giving you a growing season of approximately 228 days.

At an elevation of 883 feet, Jefferson County receives approximately 24.7 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Cilantro during the growing season.

Jefferson County, OK (Zone 7b) Long season
228 days
Last Spring Frost March 26
228 growing days
First Fall Frost November 9

Jefferson County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (131 days to spare)
Start indoors: Feb 9 Transplant: Mar 9 🍅 Harvest: Apr 20 – Jun 22
Recommended (50%) ✓ Fits season (130 days to spare)
Start indoors: Feb 19 Transplant: Mar 19 🍅 Harvest: Apr 30 – Jul 2
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Mar 11 Transplant: Apr 8 🍅 Harvest: May 20 – Jul 22

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 Jefferson County

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

Soil pH

Your soil pH (6.6โ€“7.5) is more alkaline than Cilantro prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) โ€” Cilantro will thrive.

How to Plant Cilantro

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Cilantro

6
successive plantings in your 228-day season

Sow every 4.6 weeks. Last sowing by Sep 10 to harvest before frost.

For a dedicated fall crop, sow by Aug 31.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 91 gal / 100 sq ft

Monthly Watering Guide for Cilantro

Cilantro needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Cilantro Needs Rainfall You Supplement Action
Jan โ€” 0.6" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar 2.2" 1.7" 0.5" ๐Ÿ’ง Light watering
Apr 2.2" 2.7" 0" โœ… Rainfall sufficient
May 2.2" 3.2" 0" โœ… Rainfall sufficient
Jun 2.2" 4" 0" โœ… Rainfall sufficient
Jul 2.2" 3.1" 0" โœ… Rainfall sufficient
Aug 2.2" 3.2" 0" โœ… Rainfall sufficient
Sep 2.2" 2.1" 0.1" ๐Ÿ’ง Light watering
Oct 2.2" 1.6" 0.6" ๐Ÿ’ง Light watering
Nov 2.2" 0.8" 1.4" ๐Ÿšฟ Regular watering
Dec โ€” 0.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Jefferson County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Cilantro 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.

Cilantro needs ~912 GDD — county provides 4,161 GDD Excellent fit

Cilantro Planting Timeline โ€” Jefferson County, OK

Cilantro Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 โ€“ Mar 5
Transplant Outdoors March 19 Mar 19 โ€“ Apr 2
Direct Sow March 12 Mar 12 โ€“ Apr 2
Harvest April 30 Apr 30 โ€“ Jul 2
Fall Sowing August 31 Aug 31 โ€“ Sep 14

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow Harvest
May Harvest
June Harvest
July Harvest
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

228 days in Jefferson County

Growing Tips for Cilantro in Jefferson County

Direct sow Cilantro outdoors after March 26 in Jefferson County when soil has warmed and frost danger has passed.

Summer highs in Jefferson County reach 91ยฐF โ€” grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 228.0-day season in Jefferson County allows multiple plantings of Cilantro. Sow every 20.0 days for continuous harvest.

Common pests for Cilantro in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cilantro in Jefferson County, OK?

Jefferson County is in Zone 7b with an average last frost of March 26. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, OK?

Jefferson County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 26 and first fall frost is November 9.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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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 Jefferson County, OK. Local conditions may vary. Last updated: April 2026.