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When to plant Calendula in Lake County, MN

Lake County's 103-day season only supports one Calendula planting per year. Sow between May 18 and June 8 for the best chance at full maturity before September 12.

When to Plant Calendula in Lake County, MN

Lake County, Minnesota Zone 4a June

Lake County, Minnesota gardeners: here's your June plan

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 June 1
Avg. first frost September 12
Soil temp (4") 63°F
Watering Low
Pest pressure Moderate
Daylight 15.7 hrs
  1. Get calendula in the ground

    Frost risk is low now in Lake County, Minnesota. If you've been covering beds overnight, you can stop.

Coming up in July — start thinking about
  • Starting indoors: calendula
  • 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.

Lake County, Minnesota is in USDA Zone 4a. The average last spring frost is June 1 and the first fall frost is September 12, giving you a growing season of approximately 103 days.

At an elevation of 1,191 feet, Lake County receives approximately 36.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°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
Lake County, MN (Zone 4a) Short season
103 days
Last Spring Frost June 1
103 growing days
First Fall Frost September 12

Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 1 Transplant: May 20 🌸 Bloom: Jul 8 – Sep 23
Recommended (50%) ✗ May not fit
Start indoors: Apr 13 Transplant: Jun 1 🌸 Bloom: Jul 20 – Oct 5
Safe Start (90%) ✗ May not fit
Start indoors: Apr 30 Transplant: Jun 18 🌸 Bloom: Aug 6 – Oct 22

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 Lake County

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

Soil pH

Your soil pH (5.9–6.8) is within Calendula's preferred range (5.5–7.0).

Soil Texture

The silt loam soil in Lake 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 (5.1%) — Calendula will thrive.

How to Plant Calendula

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

Succession Planting Calendula

2
successive plantings in your 103-day season

Sow every 5.7 weeks. Last sowing by Jul 04 to harvest before frost.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
1.5″/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 1.7" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 3.2" 0" ❄️ Dormant
May 4.6" 0" ❄️ Dormant
Jun 2.2" 5.2" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 4.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3" 0" ✅ Rainfall sufficient
Oct 2.4" 0" ❄️ Dormant
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Lake 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 ~645 GDD — county provides 1,107 GDD Excellent fit

Calendula Planting Timeline — Lake County, MN

Calendula Planting Calendar

Activity When Date Range
Start Indoors April 13 Apr 13 – Apr 27
Transplant Outdoors June 1 Jun 1 – Jun 15
Direct Sow May 18 May 18 – Jun 8
Bloom July 20 Jul 20 – Oct 5

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

Month-by-Month Timeline

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

📆 Growing Season

103 days in Lake County

Growing Tips for Calendula in Lake County

Direct sow Calendula outdoors after June 01 in Lake 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 Lake County, MN?

Lake County is in Zone 4a with an average last frost of June 1. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, MN?

Lake County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is June 1 and first fall frost is September 12.

When should I plant Calendula in Lake County, MN?

In Lake County, MN, plant Calendula after the last frost (around June 1) and before the first frost (around September 12). Best results when soil holds above 50°F.

What growing zone is Lake County, MN for Calendula?

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

Can Calendula grow in Lake County's climate?

Yes — Calendula grows well in Lake County's temperate climate. Lake County averages a 103-day frost-free season, with last frost around June 1 and first frost around September 12.

🌱

Your Lake County Garden Planner — Free

A 22-page printable planner built for Lake County (Zone 4a). 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 Lake County, MN. 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.