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When to plant Calendula in Jo Daviess County County,

Calendula planted in Jo Daviess County County between April 3 and April 24 matures in 70 days — well before the October 11 first frost.

When to Plant Calendula in Jo Daviess County, IL

Jo Daviess County, Illinois Zone 5a June

Top priorities for Jo Daviess County, Illinois gardeners in June

Welcome to June in Zone 5a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 24
Avg. first frost October 11
Soil temp (4") 69°F
Watering Low
Pest pressure High
Daylight 15.1 hrs
  1. Start calendula indoors

    Label every cell. You will absolutely forget which is which otherwise.

  2. Pick calendula

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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.

Jo Daviess County, Illinois is in USDA Zone 5a. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 501 feet, Jo Daviess County receives approximately 35.4 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
Jo Daviess County, IL (Zone 5a) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11
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Jo Daviess County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Start indoors: Mar 5 Transplant: Apr 16 🌸 Bloom: Jun 4 – Aug 27
Recommended (50%) ✓ Fits season (37 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🌸 Bloom: Jun 12 – Sep 4
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Mar 28 Transplant: May 9 🌸 Bloom: Jun 27 – Sep 19

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 Jo Daviess County

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

Soil pH

Your soil pH (5.9–7.3) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Calendula will thrive.

How to Plant Calendula

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

Succession Planting Calendula

4
successive plantings in your 170-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
0.9″/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 1.3" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 2.2" 3.2" 0" ✅ Rainfall sufficient
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 4.3" 0" ✅ Rainfall sufficient
Jul 2.2" 4.2" 0" ✅ Rainfall sufficient
Aug 2.2" 3.9" 0" ✅ Rainfall sufficient
Sep 2.2" 3.1" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 2.2" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jo Daviess 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 2,592 GDD Excellent fit

Calendula Planting Timeline — Jo Daviess County, IL

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 – Mar 27
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 3 Apr 3 – Apr 24
Bloom June 12 Jun 12 – Sep 4

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 5a

📆 Growing Season

170 days in Jo Daviess County

Growing Tips for Calendula in Jo Daviess County

Direct sow Calendula outdoors after April 24 in Jo Daviess 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 Jo Daviess County, IL?

Jo Daviess County is in Zone 5a with an average last frost of April 24. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jo Daviess County, IL?

Jo Daviess County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 24 and first fall frost is October 11.

When should I plant Calendula in Jo Daviess County, ?

In Jo Daviess County, , plant Calendula after the last frost (around April 24) and before the first frost (around October 11). Best results when soil holds above 50°F.

What growing zone is Jo Daviess County, for Calendula?

Jo Daviess County sits in USDA Zone 5a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Jo Daviess County's climate?

Yes — Calendula grows well in Jo Daviess County's temperate climate. Jo Daviess County averages a 170-day frost-free season, with last frost around April 24 and first frost around October 11.

🌱

Your Jo Daviess County Garden Planner — Free

A 22-page printable planner built for Jo Daviess County (Zone 5a). 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 Jo Daviess County, IL. 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.