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When to plant Calendula in Ray County County,

The best window to plant Calendula in Ray County County, is March 18–April 8, when soil warms to 50°F. Last frost typically hits April 15; first frost October 25.

When to Plant Calendula in Ray County, MO

Ray County, Missouri Zone 6a June

June to-do list for Ray County, Missouri

Each item below is timed to Ray County, Missouri's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 15
Avg. first frost October 25
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Collect calendula at their peak

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

To set up a strong July, finish these tasks
  • 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.

Ray County, Missouri is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 25, giving you a growing season of approximately 193 days.

At an elevation of 747 feet, Ray County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Calendula during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Ray County, MO (Zone 6a) Moderate season
193 days
Last Spring Frost April 15
193 growing days
First Fall Frost October 25
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Ray County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.6

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (53 days to spare)
Start indoors: Feb 23 Transplant: Apr 6 🌸 Bloom: May 25 – Aug 24
Recommended (50%) ✓ Fits season (53 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🌸 Bloom: Jun 3 – Sep 2
Safe Start (90%) ✓ Fits season (50 days to spare)
Start indoors: Mar 18 Transplant: Apr 29 🌸 Bloom: Jun 17 – Sep 16

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 Ray County

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

Soil pH

Your soil pH (5.6–6.6) is within Calendula's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is moderate (2.5%). 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 193-day season

Sow every 5.7 weeks. Last sowing by Aug 16 to harvest before frost.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/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 1.3" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 2.2" 2.8" 0" ✅ Rainfall sufficient
May 2.2" 3.9" 0" ✅ Rainfall sufficient
Jun 2.2" 4" 0" ✅ Rainfall sufficient
Jul 2.2" 3.6" 0" ✅ Rainfall sufficient
Aug 2.2" 3.1" 0" ✅ Rainfall sufficient
Sep 2.2" 3.3" 0" ✅ Rainfall sufficient
Oct 2.2" 2.3" 0" ✅ Rainfall sufficient
Nov 2.5" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Ray 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 ~1,140 GDD — county provides 3,667 GDD Excellent fit

Calendula Planting Timeline — Ray County, MO

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow March 18 Mar 18 – Apr 8
Bloom June 3 Jun 3 – Sep 2

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
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: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

193 days in Ray County

Growing Tips for Calendula in Ray County

Direct sow Calendula outdoors after April 15 in Ray 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 Ray County, MO?

Ray County is in Zone 6a with an average last frost of April 15. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ray County, MO?

Ray County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 25.

When should I plant Calendula in Ray County County, ?

In Ray County County, , plant Calendula after the last frost (around April 15) and before the first frost (around October 25). Best results when soil holds above 50°F.

What growing zone is Ray County County, for Calendula?

Ray County 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 Ray County County's climate?

Yes — Calendula grows well in Ray County County's temperate climate. Ray County County averages a 193-day frost-free season, with last frost around April 15 and first frost around October 25.

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Your Ray County Garden Planner — Free

A 22-page printable planner built for Ray 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 Ray 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.