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When to Plant Calendula in Callahan County, TX

Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.

Callahan County, Texas is in USDA Zone 8a. The average last spring frost is March 21 and the first fall frost is November 16, giving you a growing season of approximately 240 days.

At an elevation of 4,241 feet, Callahan County receives approximately 59.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Calendula during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Calendula root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Callahan County, TX (Zone 8a) Long season
240 days
Last Spring Frost March 21
240 growing days
First Fall Frost November 16

Callahan County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.4

Drainage

Well Drained

Monthly Watering Guide for Calendula

Calendula needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Calendula Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 4.3" 3.3" 1" 💧 Light watering
Apr 4.3" 5.9" 0" ✅ Rainfall sufficient
May 4.3" 7.8" 0" ✅ Rainfall sufficient
Jun 4.3" 11" 0" ✅ Rainfall sufficient
Jul 4.3" 8.5" 0" ✅ Rainfall sufficient
Aug 4.3" 6.1" 0" ✅ Rainfall sufficient
Sep 4.3" 5.7" 0" ✅ Rainfall sufficient
Oct 4.3" 3.8" 0.5" 💧 Light watering
Nov 4.3" 1.8" 2.5" 🚿 Regular watering
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Callahan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Calendula Planting Timeline — Callahan County, TX

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors March 7 Mar 7 – Mar 21
Direct Sow February 7 Feb 7 – Feb 28
Bloom April 25 Apr 25 – Sep 5
Fall Sowing September 7 Sep 7 – Sep 21

Plant 0.3" deep · 9" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 8a

📆 Growing Season

240 days in Callahan County

Growing Tips for Callahan County

Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Calendula in Callahan County, TX?

Callahan County is in Zone 8a with an average last frost of March 21. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Callahan County, TX?

Callahan County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 21 and first fall frost is November 16.

🌱

Your Callahan County Garden Planner — Free

A 22-page printable planner built for Callahan County (Zone 8a). 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 Callahan County, TX. Local conditions may vary. Last updated: July 2026.

Sources & credits

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