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When to Plant Cumin in Robertson County, TX

Cumin is a warm-season annual herb whose seeds are one of the most widely used spices globally. It requires a long, hot growing season of 3-4 months.

Robertson County, Texas is in USDA Zone 8a. The average last spring frost is March 7 and the first fall frost is November 16, giving you a growing season of approximately 254 days.

At an elevation of 85 feet, Robertson County receives approximately 61.1 inches of rainfall annually with predominantly clay soil. Summer highs average 93ยฐF, providing good warmth for Cumin during the growing season. Clay soil retains moisture well for Cumin, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cumin root diseases.

Robertson County, TX (Zone 8a) Long season
254 days
Last Spring Frost March 7
254 growing days
First Fall Frost November 16

Robertson County Soil Profile

Soil Type

Clay

Soil pH

6.8-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (95 days to spare)
Start indoors: Jan 24 Transplant: Feb 21 🍅 Harvest: Jun 6 – Aug 8
Recommended (50%) ✓ Fits season (93 days to spare)
Start indoors: Jan 31 Transplant: Feb 28 🍅 Harvest: Jun 13 – Aug 15
Safe Start (90%) ✓ Fits season (87 days to spare)
Start indoors: Mar 3 Transplant: Mar 31 🍅 Harvest: Jul 14 – Sep 15

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 Robertson County

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

Soil pH

Your soil pH (6.8โ€“8.0) is within Cumin's preferred range (6.0โ€“8.0).

Soil Texture

Heavy clay soil (45% clay) in Robertson County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Cumin.

How to Plant Cumin

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

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

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/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 Cumin

Cumin 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 Cumin Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 2.2" 0" โ„๏ธ Dormant
Mar 2.2" 4.3" 0" โœ… Rainfall sufficient
Apr 2.2" 5.6" 0" โœ… Rainfall sufficient
May 2.2" 10" 0" โœ… Rainfall sufficient
Jun 2.2" 8.4" 0" โœ… Rainfall sufficient
Jul 2.2" 8.3" 0" โœ… Rainfall sufficient
Aug 2.2" 8.2" 0" โœ… Rainfall sufficient
Sep 2.2" 5.2" 0" โœ… Rainfall sufficient
Oct 2.2" 3.7" 0" โœ… Rainfall sufficient
Nov 2.2" 2.3" 0" โœ… Rainfall sufficient
Dec โ€” 1.6" 0" โ„๏ธ Dormant

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

Cumin 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.

Cumin needs ~2,172 GDD — county provides 5,016 GDD Excellent fit

Cumin Planting Timeline โ€” Robertson County, TX

Cumin Planting Calendar

Activity When Date Range
Start Indoors January 31 Jan 31 โ€“ Feb 14
Transplant Outdoors February 28 Feb 28 โ€“ Mar 14
Direct Sow February 21 Feb 21 โ€“ Mar 14
Harvest June 13 Jun 13 โ€“ Aug 15
Fall Sowing September 7 Sep 7 โ€“ Sep 21

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

100โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“8 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

254 days in Robertson County

Growing Tips for Cumin in Robertson County

Direct sow Cumin outdoors after March 07 in Robertson County when soil has warmed and frost danger has passed.

With Robertson County's clay soil (45% clay), work in 3-4 inches of compost before planting Cumin. Avoid tilling when soil is wet to prevent compaction.

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

General growing tips

Start seeds indoors 4 weeks before last frost. Transplant after all danger of frost. Harvest when seed heads turn brown. Requires consistent warmth for proper seed development.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cumin in Robertson County, TX?

Robertson County is in Zone 8a with an average last frost of March 7. Plan your Cumin planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Robertson County, TX?

Robertson County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 7 and first fall frost is November 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Robertson County gardeners in Zone 8a 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 Robertson County, TX. Local conditions may vary. Last updated: April 2026.