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When to Plant Calendula in Ozaukee County, WI

Ozaukee County, Wisconsin Zone 5b June

What to do in June

Your Ozaukee County, Wisconsin 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 27
Avg. first frost October 11
Soil temp (4") 68°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Start calendula under lights

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

  2. It's harvest week for calendula

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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.

Ozaukee County, Wisconsin is in USDA Zone 5b. The average last spring frost is April 27 and the first fall frost is October 11, giving you a growing season of approximately 167 days.

At an elevation of 1,277 feet, Ozaukee County receives approximately 32.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°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
Ozaukee County, WI (Zone 5b) Moderate season
167 days
Last Spring Frost April 27
167 growing days
First Fall Frost October 11
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Ozaukee County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.1

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🌸 Bloom: Jun 12 – Sep 11
Recommended (50%) ✓ Fits season (27 days to spare)
Start indoors: Mar 16 Transplant: Apr 27 🌸 Bloom: Jun 15 – Sep 14
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Apr 1 Transplant: May 13 🌸 Bloom: Jul 1 – 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 Ozaukee County

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

Soil pH

Your soil pH (6.1–7.1) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Calendula.

Organic Matter

Organic matter is excellent (4.7%) — 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 167-day season

Sow every 5.7 weeks. Last sowing by Aug 02 to harvest before frost.

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 1.4" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.2" 2.7" 0" ✅ Rainfall sufficient
May 2.2" 3.3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.9" 0" ✅ Rainfall sufficient
Jul 2.2" 4" 0" ✅ Rainfall sufficient
Aug 2.2" 3.8" 0" ✅ Rainfall sufficient
Sep 2.2" 2.9" 0" ✅ Rainfall sufficient
Oct 2.2" 2.5" 0" ✅ Rainfall sufficient
Nov 2.3" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Ozaukee 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 ~780 GDD — county provides 2,171 GDD Excellent fit

Calendula Planting Timeline — Ozaukee County, WI

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 16 Mar 16 – Mar 30
Transplant Outdoors April 27 Apr 27 – May 11
Direct Sow April 6 Apr 6 – Apr 27
Bloom June 15 Jun 15 – Sep 14

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors
June Bloom
July Bloom
August Bloom
September 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 5b

📆 Growing Season

167 days in Ozaukee County

Growing Tips for Calendula in Ozaukee County

Direct sow Calendula outdoors after April 27 in Ozaukee 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 Ozaukee County, WI?

Ozaukee County is in Zone 5b with an average last frost of April 27. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ozaukee County, WI?

Ozaukee County, Wisconsin is in USDA Hardiness Zone 5b. The average last spring frost is April 27 and first fall frost is October 11.

🌱

Your Ozaukee County Garden Planner — Free

A 22-page printable planner built for Ozaukee County (Zone 5b). 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 Ozaukee County, WI. 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.