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When to plant Calendula in Genesee County County,

Plant Calendula in Genesee County County from March 31 to April 21 in spring. Genesee County County sits in USDA Zone 6a, with last frost around April 28 and first frost on October 17.

When to Plant Calendula in Genesee County, MI

Genesee County, Michigan Zone 6a June

June in Genesee County, Michigan — your action list

Here's what deserves your attention in Genesee County, Michigan this month. Everything below is tailored to Zone 6a and timed around your local frost dates.

Avg. last frost April 28
Avg. first frost October 17
Soil temp (4") 69°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Indoor seed-starting week for calendula

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Basket week: calendula

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Get ahead of July
  • 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.

Genesee County, Michigan is in USDA Zone 6a. The average last spring frost is April 28 and the first fall frost is October 17, giving you a growing season of approximately 172 days.

At an elevation of 1,023 feet, Genesee County receives approximately 39.6 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
Genesee County, MI (Zone 6a) Moderate season
172 days
Last Spring Frost April 28
172 growing days
First Fall Frost October 17

Genesee County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Mar 15 Transplant: Apr 26 🌸 Bloom: Jun 14 – Sep 13
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Mar 17 Transplant: Apr 28 🌸 Bloom: Jun 16 – Sep 15
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 Genesee County

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

Soil pH

Your soil pH (5.9–7.2) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

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

4
successive plantings in your 172-day season

Sow every 5.7 weeks. Last sowing by Aug 08 to harvest before frost.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/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 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 3.2" 0" ❄️ Dormant
Apr 2.2" 3.7" 0" ✅ Rainfall sufficient
May 2.2" 4.9" 0" ✅ Rainfall sufficient
Jun 2.2" 5.1" 0" ✅ Rainfall sufficient
Jul 2.2" 4.4" 0" ✅ Rainfall sufficient
Aug 2.2" 3.8" 0" ✅ Rainfall sufficient
Sep 2.2" 3.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 2.6" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Genesee 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 2,236 GDD Excellent fit

Calendula Planting Timeline — Genesee County, MI

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 – Mar 31
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow March 31 Mar 31 – Apr 21
Bloom June 16 Jun 16 – Sep 15

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Transplant Outdoors
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 6a

📆 Growing Season

172 days in Genesee County

Growing Tips for Calendula in Genesee County

Direct sow Calendula outdoors after April 28 in Genesee 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 Genesee County, MI?

Genesee County is in Zone 6a with an average last frost of April 28. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Genesee County, MI?

Genesee County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 28 and first fall frost is October 17.

When should I plant Calendula in Genesee County, ?

In Genesee County, , plant Calendula after the last frost (around April 28) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Genesee County, for Calendula?

Genesee County sits in USDA Zone 6a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Genesee County's climate?

Yes — Calendula grows well in Genesee County's temperate climate. Genesee County averages a 172-day frost-free season, with last frost around April 28 and first frost around October 17.

🌱

Your Genesee County Garden Planner — Free

A 22-page printable planner built for Genesee County (Zone 6a). 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 Genesee 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.