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When to Plant Cilantro in Cameron County, TX

Cameron County, Texas Zone 10a May

May in Cameron County, Texas — your action list

May is a pivotal month for Cameron County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost February 4
Avg. first frost December 22
Soil temp (4") 68°F
Watering Low
Pest pressure High
Daylight 13.3 hrs
  1. Bring in the cilantro

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

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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.

Cameron County, Texas is in USDA Zone 10a. The average last spring frost is February 4 and the first fall frost is December 22, giving you a growing season of approximately 321 days.

At an elevation of 4,025 feet, Cameron County receives approximately 58.6 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Cilantro may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cilantro root diseases.

Cameron County, TX (Zone 10a) Year-round
321 days
Last Spring Frost February 4
321 growing days
First Fall Frost December 22

Cameron County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (235 days to spare)
Start indoors: Dec 20 Transplant: Jan 10 🍅 Harvest: Feb 21 – Apr 25
Recommended (50%) ✓ Fits season (223 days to spare)
Start indoors: Jan 7 Transplant: Jan 28 🍅 Harvest: Mar 11 – May 13
Safe Start (90%) ✓ Fits season (200 days to spare)
Start indoors: Feb 4 Transplant: Feb 25 🍅 Harvest: Apr 8 – Jun 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 Cameron County

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

Soil pH

Your soil pH (6.7–7.8) is more alkaline than Cilantro prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Cameron County is excellent for Cilantro — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Cilantro.

How to Plant Cilantro

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Cilantro

9
successive plantings in your 321-day season

Sow every 4.6 weeks. Last sowing by Oct 23 to harvest before frost.

For a dedicated fall crop, sow by Oct 27.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 1.6" 0" ❄️ Dormant
Feb 2.2" 2.2" 0" ✅ Rainfall sufficient
Mar 2.2" 3.1" 0" ✅ Rainfall sufficient
Apr 2.2" 6.1" 0" ✅ Rainfall sufficient
May 2.2" 9.2" 0" ✅ Rainfall sufficient
Jun 2.2" 9.1" 0" ✅ Rainfall sufficient
Jul 2.2" 7.5" 0" ✅ Rainfall sufficient
Aug 2.2" 6.9" 0" ✅ Rainfall sufficient
Sep 2.2" 5.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.8" 0" ✅ Rainfall sufficient
Nov 2.2" 2.1" 0.1" 💧 Light watering
Dec 2.2" 1.4" 0.8" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Cameron County). Supplement amounts are based on average rainfall — 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" — 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.

Cilantro needs ~1,362 GDD — county provides 8,774 GDD Excellent fit

Cilantro Planting Timeline — Cameron County, TX

Cilantro Planting Calendar

Activity When Date Range
Start Indoors January 7 Jan 7 – Jan 21
Transplant Outdoors January 28 Jan 28 – Feb 11
Direct Sow January 14 Jan 14 – Feb 4
Harvest March 11 Mar 11 – May 13
Fall Sowing October 27 Oct 27 – Nov 10

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 10a

📆 Growing Season

321 days in Cameron County

Growing Tips for Cilantro in Cameron County

Direct sow Cilantro outdoors after February 04 in Cameron County when soil has warmed and frost danger has passed.

Summer highs in Cameron County reach 103°F — grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 322.0-day season in Cameron 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.

With 59" of annual rainfall in Cameron County, ensure good drainage for Cilantro — excess moisture can promote root rot and fungal diseases.

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 Cameron County, TX?

Cameron County is in Zone 10a with an average last frost of February 4. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cameron County, TX?

Cameron County, Texas is in USDA Hardiness Zone 10a. The average last spring frost is February 4 and first fall frost is December 22.

🌱

Your Cameron County Garden Planner — Free

A 24-page printable planner built for Cameron County (Zone 10a). 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 Cameron County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

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