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When to plant Calendula in Jackson County County,

Plant Calendula in Jackson County County after April 12; the prime window is March 15–April 5.

When to Plant Calendula in Jackson County, MO

Jackson County, Missouri Zone 6b June

Jackson County, Missouri gardeners: here's your June plan

A quick June briefing for Jackson County, Missouri gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 12
Avg. first frost October 26
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Bring in the calendula

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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.

Jackson County, Missouri is in USDA Zone 6b. The average last spring frost is April 12 and the first fall frost is October 26, giving you a growing season of approximately 197 days.

At an elevation of 563 feet, Jackson County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Calendula during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Jackson County, MO (Zone 6b) Moderate season
197 days
Last Spring Frost April 12
197 growing days
First Fall Frost October 26

Jackson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.6

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (48 days to spare)
Start indoors: Feb 22 Transplant: Apr 5 🌸 Bloom: May 24 – Aug 30
Recommended (50%) ✓ Fits season (50 days to spare)
Start indoors: Mar 1 Transplant: Apr 12 🌸 Bloom: May 31 – Sep 6
Safe Start (90%) ✓ Fits season (44 days to spare)
Start indoors: Mar 17 Transplant: Apr 28 🌸 Bloom: Jun 16 – Sep 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 Jackson County

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

Soil pH

Your soil pH (5.2–6.6) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Calendula.

How to Plant Calendula

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

Succession Planting Calendula

4
successive plantings in your 197-day season

Sow every 5.7 weeks. Last sowing by Aug 17 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
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 3.2" 0" ❄️ Dormant
Apr 2.2" 4.2" 0" ✅ Rainfall sufficient
May 2.2" 5.4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.8" 0" ✅ Rainfall sufficient
Jul 2.2" 4.2" 0" ✅ Rainfall sufficient
Aug 2.2" 4.1" 0" ✅ Rainfall sufficient
Sep 2.2" 3.6" 0" ✅ Rainfall sufficient
Oct 2.2" 2.9" 0" ✅ Rainfall sufficient
Nov 3.2" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jackson 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 ~1,050 GDD — county provides 3,447 GDD Excellent fit

Calendula Planting Timeline — Jackson County, MO

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 1 Mar 1 – Mar 15
Transplant Outdoors April 12 Apr 12 – Apr 26
Direct Sow March 15 Mar 15 – Apr 5
Bloom May 31 May 31 – Sep 6

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 Bloom
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 6b

📆 Growing Season

197 days in Jackson County

Growing Tips for Calendula in Jackson County

Direct sow Calendula outdoors after April 12 in Jackson 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 Jackson County, MO?

Jackson County is in Zone 6b with an average last frost of April 12. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, MO?

Jackson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 12 and first fall frost is October 26.

When should I plant Calendula in Jackson County County, ?

In Jackson County County, , plant Calendula after the last frost (around April 12) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Jackson County County, for Calendula?

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

Can Calendula grow in Jackson County County's climate?

Yes — Calendula grows well in Jackson County County's temperate climate. Jackson County County averages a 197-day frost-free season, with last frost around April 12 and first frost around October 26.

🌱

Your Jackson County Garden Planner — Free

A 22-page printable planner built for Jackson County (Zone 6b). 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 Jackson County, MO. 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.