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When to plant Calendula in Dickinson County, MI

In Zone 4b (Dickinson County), direct-sow Calendula between April 28 and May 19 for spring, after the May 12 last-frost mark.

When to Plant Calendula in Dickinson County, MI

Dickinson County, Michigan Zone 4b June

June in Dickinson County, Michigan — your action list

Welcome to June in Zone 4b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 12
Avg. first frost October 9
Soil temp (4") 64°F
Watering Moderate
Pest pressure High
Daylight 15.5 hrs
  1. Fire up the seed-starting tray: calendula

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Harvest calendula as they ripen

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

Coming up in July — start thinking about
  • 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.

Dickinson County, Michigan is in USDA Zone 4b. The average last spring frost is May 12 and the first fall frost is October 9, giving you a growing season of approximately 150 days.

At an elevation of 892 feet, Dickinson County receives approximately 32.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Calendula to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Dickinson County, MI (Zone 4b) Moderate season
150 days
Last Spring Frost May 12
150 growing days
First Fall Frost October 9

Dickinson County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Mar 16 Transplant: May 4 🌸 Bloom: Jun 22 – Sep 7
Recommended (50%) ✓ Fits season (24 days to spare)
Start indoors: Mar 24 Transplant: May 12 🌸 Bloom: Jun 30 – Sep 15
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Apr 9 Transplant: May 28 🌸 Bloom: Jul 16 – 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 Dickinson County

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

Soil pH

Your soil pH (6.0–7.3) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) — Calendula will thrive.

How to Plant Calendula

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

Succession Planting Calendula

3
successive plantings in your 150-day season

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

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 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 3.3" 0" ❄️ Dormant
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 3.7" 0" ✅ Rainfall sufficient
Jul 2.2" 3.8" 0" ✅ Rainfall sufficient
Aug 2.2" 3.1" 0" ✅ Rainfall sufficient
Sep 2.2" 2.9" 0" ✅ Rainfall sufficient
Oct 2.2" 2.3" 0" ✅ Rainfall sufficient
Nov 2.1" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Dickinson 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 ~690 GDD — county provides 1,725 GDD Excellent fit

Calendula Planting Timeline — Dickinson County, MI

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 24 Mar 24 – Apr 7
Transplant Outdoors May 12 May 12 – May 26
Direct Sow April 28 Apr 28 – May 19
Bloom June 30 Jun 30 – Sep 15

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Bloom
July Bloom
August Bloom
September 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 4b

📆 Growing Season

150 days in Dickinson County

Growing Tips for Calendula in Dickinson County

Direct sow Calendula outdoors after May 12 in Dickinson 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 Dickinson County, MI?

Dickinson County is in Zone 4b with an average last frost of May 12. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dickinson County, MI?

Dickinson County, Michigan is in USDA Hardiness Zone 4b. The average last spring frost is May 12 and first fall frost is October 9.

When should I plant Calendula in Dickinson County, MI?

In Dickinson County, MI, plant Calendula after the last frost (around May 12) and before the first frost (around October 9). Best results when soil holds above 50°F.

What growing zone is Dickinson County, MI for Calendula?

Dickinson County sits in USDA Zone 4b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Dickinson County's climate?

Yes — Calendula grows well in Dickinson County's temperate climate. Dickinson County averages a 150-day frost-free season, with last frost around May 12 and first frost around October 9.

🌱

Your Dickinson County Garden Planner — Free

A 22-page printable planner built for Dickinson County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Dickinson County, MI. 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.