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When to plant Calendula in Jefferson County, AR

Jefferson County's spring Calendula window runs January 29 through February 19. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from August 31 to September 14 extends the harvest into fall.

When to Plant Calendula in Jefferson County, AR

Jefferson County, Arkansas Zone 8b June

What to do in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 19
Avg. first frost November 9
Soil temp (4") 77°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Start harvesting calendula

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Before July arrives, get these ready
  • 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.

Jefferson County, Arkansas is in USDA Zone 8b. The average last spring frost is March 19 and the first fall frost is November 9, giving you a growing season of approximately 235 days.

At an elevation of 454 feet, Jefferson County receives approximately 51.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°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
Jefferson County, AR (Zone 8b) Long season
235 days
Last Spring Frost March 19
235 growing days
First Fall Frost November 9

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7.1

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (61 days to spare)
Transplant: Feb 17 🌸 Bloom: Apr 7 – Sep 1
Recommended (50%) ✓ Fits season (60 days to spare)
Transplant: Feb 26 🌸 Bloom: Apr 16 – Sep 10
Safe Start (90%) ✓ Fits season (58 days to spare)
Transplant: Mar 18 🌸 Bloom: May 6 – Sep 30

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 Jefferson County

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

Soil pH

Your soil pH (5.3–7.1) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.5%). 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 235-day season

Sow every 5.7 weeks. Last sowing by Aug 31 to harvest before frost.

For a dedicated fall crop, sow by Aug 31.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/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 4" 0" ❄️ Dormant
Feb 3.9" 0" ❄️ Dormant
Mar 2.2" 5.4" 0" ✅ Rainfall sufficient
Apr 2.2" 3.7" 0" ✅ Rainfall sufficient
May 2.2" 4.1" 0" ✅ Rainfall sufficient
Jun 2.2" 4.3" 0" ✅ Rainfall sufficient
Jul 2.2" 5.5" 0" ✅ Rainfall sufficient
Aug 2.2" 5.1" 0" ✅ Rainfall sufficient
Sep 2.2" 3.4" 0" ✅ Rainfall sufficient
Oct 2.2" 3.7" 0" ✅ Rainfall sufficient
Nov 2.2" 4.4" 0" ✅ Rainfall sufficient
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Jefferson 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 ~1,005 GDD — county provides 3,936 GDD Excellent fit

Calendula Planting Timeline — Jefferson County, AR

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors February 26 Feb 26 – Mar 12
Direct Sow January 29 Jan 29 – Feb 19
Bloom April 16 Apr 16 – Sep 10
Fall Sowing August 31 Aug 31 – Sep 14

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

Month-by-Month Timeline

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

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 8b

📆 Growing Season

235 days in Jefferson County

Growing Tips for Calendula in Jefferson County

Direct sow Calendula outdoors after March 19 in Jefferson County when soil has warmed and frost danger has passed.

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 Jefferson County, AR?

Jefferson County is in Zone 8b with an average last frost of March 19. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, AR?

Jefferson County, Arkansas is in USDA Hardiness Zone 8b. The average last spring frost is March 19 and first fall frost is November 9.

When should I plant Calendula in Jefferson County, AR?

In Jefferson County, AR, plant Calendula after the last frost (around March 19) and before the first frost (around November 9). Best results when soil holds above 50°F.

What growing zone is Jefferson County, AR for Calendula?

Jefferson County sits in USDA Zone 8b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Jefferson County's climate?

Yes — Calendula grows well in Jefferson County's temperate climate. Jefferson County averages a 235-day frost-free season, with last frost around March 19 and first frost around November 9.

🌱

Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson County (Zone 8b). 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 Jefferson County, AR. 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.