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When to Plant Calendula in Refugio County, TX

Refugio County, Texas Zone 9b June

June in the garden — Refugio County, Texas

Your Refugio County, Texas garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost February 16
Avg. first frost December 6
Soil temp (4") 87°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Harvest calendula as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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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.

Refugio County, Texas is in USDA Zone 9b. The average last spring frost is February 16 and the first fall frost is December 6, giving you a growing season of approximately 293 days.

At an elevation of 1,000 feet, Refugio County receives approximately 68.4 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Calendula may need afternoon shade and extra watering during peak heat. 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
Refugio County, TX (Zone 9b) Year-round
293 days
Last Spring Frost February 16
293 growing days
First Fall Frost December 6
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Refugio County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.2

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (181 days to spare)
Transplant: Dec 29 🌸 Bloom: Feb 9 – Jun 1
Recommended (50%) ✓ Fits season (174 days to spare)
Transplant: Jan 12 🌸 Bloom: Feb 23 – Jun 15
Safe Start (90%) ✓ Fits season (166 days to spare)
Transplant: Feb 5 🌸 Bloom: Mar 19 – Jul 9

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 Refugio County

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

Soil pH

Your soil pH (6.7–7.2) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.0%). Annual compost additions will help Calendula.

How to Plant Calendula

0.3"
Planting Depth
9"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Calendula

7
successive plantings in your 293-day season

Sow every 5.7 weeks. Last sowing by Sep 27 to harvest before frost.

For a dedicated fall crop, sow by Sep 13.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Calendula

Calendula 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 Calendula Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 2.2" 2.1" 0.1" 💧 Light watering
Mar 2.2" 3.9" 0" ✅ Rainfall sufficient
Apr 2.2" 8.3" 0" ✅ Rainfall sufficient
May 2.2" 9.2" 0" ✅ Rainfall sufficient
Jun 2.2" 11.3" 0" ✅ Rainfall sufficient
Jul 2.2" 9.3" 0" ✅ Rainfall sufficient
Aug 2.2" 8" 0" ✅ Rainfall sufficient
Sep 2.2" 5.7" 0" ✅ Rainfall sufficient
Oct 2.2" 4.5" 0" ✅ Rainfall sufficient
Nov 2.2" 2.4" 0" ✅ Rainfall sufficient
Dec 2.2" 1.8" 0.4" 💧 Light watering

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

Calendula 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.

Calendula needs ~1,635 GDD — county provides 8,011 GDD Excellent fit

Calendula Planting Timeline — Refugio County, TX

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors January 12 Jan 12 – Jan 26
Direct Sow December 15 Dec 15 – Jan 5
Bloom February 23 Feb 23 – Jun 15
Fall Sowing September 13 Sep 13 – Sep 27

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

293 days in Refugio County

Growing Tips for Calendula in Refugio County

Direct sow Calendula outdoors after February 16 in Refugio County when soil has warmed and frost danger has passed.

With summer highs reaching 103°F in Refugio County, provide afternoon shade for Calendula and water deeply in the morning.

Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Refugio County, TX?

Refugio County is in Zone 9b with an average last frost of February 16. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Refugio County, TX?

Refugio County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 16 and first fall frost is December 6.

🌱

Your Refugio County Garden Planner — Free

A 22-page printable planner built for Refugio County (Zone 9b). 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 Refugio County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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