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When to plant Calendula in Clark County, IN

Clark County gardeners should plant Calendula between March 6 and March 27 in spring. With Clark County's Zone 7a climate (last frost April 10), Calendula needs 50–70 days to mature — plant by August 13 for a full harvest. A second sowing from August 27 to September 10 extends the harvest into fall.

When to Plant Calendula in Clark County, IN

Clark County, Indiana Zone 7a June

June in Clark County, Indiana — your action list

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

Avg. last frost April 10
Avg. first frost October 22
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.7 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.

July will be here before you know it — start on
  • 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.

Clark County, Indiana is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 22, giving you a growing season of approximately 195 days.

At an elevation of 1,265 feet, Clark County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Calendula during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Clark County, IN (Zone 7a) Moderate season
195 days
Last Spring Frost April 10
195 growing days
First Fall Frost October 22

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.7

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (42 days to spare)
Start indoors: Feb 21 Transplant: Apr 4 🌸 Bloom: May 23 – Sep 5
Recommended (50%) ✓ Fits season (41 days to spare)
Start indoors: Feb 27 Transplant: Apr 10 🌸 Bloom: May 29 – Sep 11
Safe Start (90%) ✓ Fits season (38 days to spare)
Start indoors: Mar 19 Transplant: Apr 30 🌸 Bloom: Jun 18 – Oct 1

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 Clark County

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

Soil pH

Your soil pH (5.8–6.7) is within Calendula's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — Calendula will thrive.

How to Plant Calendula

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Calendula

4
successive plantings in your 195-day season

Sow every 5.7 weeks. Last sowing by Aug 13 to harvest before frost.

For a dedicated fall crop, sow by Aug 27.

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 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 2.2" 3.8" 0" ✅ Rainfall sufficient
May 2.2" 4.5" 0" ✅ Rainfall sufficient
Jun 2.2" 4.5" 0" ✅ Rainfall sufficient
Jul 2.2" 4.1" 0" ✅ Rainfall sufficient
Aug 2.2" 3.5" 0" ✅ Rainfall sufficient
Sep 2.2" 2.8" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 3" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Clark 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 ~915 GDD — county provides 2,973 GDD Excellent fit

Calendula Planting Timeline — Clark County, IN

Calendula Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow March 6 Mar 6 – Mar 27
Bloom May 29 May 29 – Sep 11
Fall Sowing August 27 Aug 27 – Sep 10

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Direct Sow
April Transplant Outdoors
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: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

195 days in Clark County

Growing Tips for Calendula in Clark County

Direct sow Calendula outdoors after April 10 in Clark 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 Clark County, IN?

Clark County is in Zone 7a with an average last frost of April 10. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clark County, IN?

Clark County, Indiana is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 22.

When should I plant Calendula in Clark County, IN?

In Clark County, IN, plant Calendula after the last frost (around April 10) and before the first frost (around October 22). Best results when soil holds above 50°F.

What growing zone is Clark County, IN for Calendula?

Clark County sits in USDA Zone 7a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Clark County's climate?

Yes — Calendula grows well in Clark County's temperate climate. Clark County averages a 195-day frost-free season, with last frost around April 10 and first frost around October 22.

🌱

Your Clark County Garden Planner — Free

A 22-page printable planner built for Clark County (Zone 7a). 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 Clark County, IN. 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.