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When to Plant Calendula in Howard County, TX

Howard County, Texas Zone 8a June

Howard County, Texas gardeners: here's your June plan

Your garden in Howard County, Texas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost March 26
Avg. first frost November 12
Soil temp (4") 68°F
Watering High
Pest pressure High
Daylight 14.1 hrs
  1. Harvest calendula as they ripen

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Looking ahead to July
  • First harvests: calendula

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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.

Howard County, Texas is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 12, giving you a growing season of approximately 231 days.

At an elevation of 3,918 feet, Howard County receives approximately 59.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Calendula may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Calendula will need more frequent watering and organic matter to retain nutrients. 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
Howard County, TX (Zone 8a) Long season
231 days
Last Spring Frost March 26
231 growing days
First Fall Frost November 12
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Howard County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.9-8.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (62 days to spare)
Transplant: Mar 4 🌸 Bloom: Apr 22 – Sep 2
Recommended (50%) ✓ Fits season (63 days to spare)
Transplant: Mar 12 🌸 Bloom: Apr 30 – Sep 10
Safe Start (90%) ✓ Fits season (58 days to spare)
Transplant: Mar 31 🌸 Bloom: May 19 – Sep 29

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 Howard County

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

Soil pH

Your soil pH (7.9–8.3) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Howard County warms quickly in spring but drains fast. Calendula will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Calendula.

How to Plant Calendula

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

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

Succession Planting Calendula

5
successive plantings in your 231-day season

Sow every 5.7 weeks. Last sowing by Sep 03 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

Calendula Water Budget

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

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

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 4.6" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 2.2" 3.2" 0" ✅ Rainfall sufficient
Apr 2.2" 2.3" 0" ✅ Rainfall sufficient
May 2.2" 1.5" 0.7" 💧 Light watering
Jun 2.2" 2" 0.2" 💧 Light watering
Jul 2.2" 10.3" 0" ✅ Rainfall sufficient
Aug 2.2" 11.5" 0" ✅ Rainfall sufficient
Sep 2.2" 8.2" 0" ✅ Rainfall sufficient
Oct 2.2" 5.2" 0" ✅ Rainfall sufficient
Nov 2.2" 3.5" 0" ✅ Rainfall sufficient
Dec 3.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Howard 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 ~1,455 GDD — county provides 5,601 GDD Excellent fit

Calendula Planting Timeline — Howard County, TX

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors March 12 Mar 12 – Mar 26
Direct Sow February 12 Feb 12 – Mar 5
Bloom April 30 Apr 30 – Sep 10
Fall Sowing September 3 Sep 3 – Sep 17

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 8a

📆 Growing Season

231 days in Howard County

Growing Tips for Calendula in Howard County

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

Sandy soil in Howard County dries quickly — mulch Calendula with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 99°F in Howard 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 Howard County, TX?

Howard County is in Zone 8a with an average last frost of March 26. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Howard County, TX?

Howard County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 12.

🌱

Your Howard County Garden Planner — Free

A 22-page printable planner built for Howard 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 Howard 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.