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When to Plant Calendula in Duplin County, NC

Duplin County, North Carolina Zone 8a June

This month in Duplin County, North Carolina

A quick June briefing for Duplin County, North Carolina gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 23
Avg. first frost November 8
Soil temp (4") 81°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Harvest calendula as they ripen

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Get ahead of 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.

Duplin County, North Carolina is in USDA Zone 8a. The average last spring frost is March 23 and the first fall frost is November 8, giving you a growing season of approximately 230 days.

At an elevation of 829 feet, Duplin County receives approximately 45.9 inches of rainfall annually with predominantly clay loam soil. Summer highs average 96°F, so Calendula may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Calendula, but amend with compost to improve drainage and prevent root rot.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Duplin County, NC (Zone 8a) Long season
230 days
Last Spring Frost March 23
230 growing days
First Fall Frost November 8
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Duplin County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (66 days to spare)
Transplant: Feb 28 🌸 Bloom: Apr 18 – Aug 29
Recommended (50%) ✓ Fits season (62 days to spare)
Transplant: Mar 9 🌸 Bloom: Apr 27 – Sep 7
Safe Start (90%) ✓ Fits season (57 days to spare)
Transplant: Apr 3 🌸 Bloom: May 22 – Oct 2

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 Duplin County

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

Soil pH

Your soil pH (5.3–6.5) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help 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 230-day season

Sow every 5.7 weeks. Last sowing by Aug 30 to harvest before frost.

For a dedicated fall crop, sow by Aug 30.

Calendula 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 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 3.6" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 2.2" 4" 0" ✅ Rainfall sufficient
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 4" 0" ✅ Rainfall sufficient
Jul 2.2" 4.7" 0" ✅ Rainfall sufficient
Aug 2.2" 5.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3.1" 0" ✅ Rainfall sufficient
Oct 2.2" 3.1" 0" ✅ Rainfall sufficient
Nov 2.2" 3.2" 0" ✅ Rainfall sufficient
Dec 4.4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Duplin 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 ~1,320 GDD — county provides 5,060 GDD Excellent fit

Calendula Planting Timeline — Duplin County, NC

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors March 9 Mar 9 – Mar 23
Direct Sow February 9 Feb 9 – Mar 2
Bloom April 27 Apr 27 – Sep 7
Fall Sowing August 30 Aug 30 – Sep 13

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 Fall Sowing 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: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

230 days in Duplin County

Growing Tips for Calendula in Duplin County

Direct sow Calendula outdoors after March 23 in Duplin County when soil has warmed and frost danger has passed.

With Duplin County's clay soil (26% clay), work in 3-4 inches of compost before planting Calendula. Avoid tilling when soil is wet to prevent compaction.

With summer highs reaching 96°F in Duplin 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 Duplin County, NC?

Duplin County is in Zone 8a with an average last frost of March 23. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Duplin County, NC?

Duplin County, North Carolina is in USDA Hardiness Zone 8a. The average last spring frost is March 23 and first fall frost is November 8.

🌱

Your Duplin County Garden Planner — Free

A 22-page printable planner built for Duplin 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 Duplin County, NC. 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.