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When to plant Calendula in Atchison County County,

Atchison County County sits in USDA Zone 5b. Plant Calendula between April 1 (after last frost on April 22) and April 22.

When to Plant Calendula in Atchison County, MO

Atchison County, Missouri Zone 5b June

Your June gardening checklist

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Atchison County, Missouri.

Avg. last frost April 22
Avg. first frost October 13
Soil temp (4") 68°F
Watering Low
Pest pressure High
Daylight 14.9 hrs
  1. Start calendula indoors

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Harvest calendula as they ripen

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Before July arrives, get these ready
  • 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.

Atchison County, Missouri is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 13, giving you a growing season of approximately 174 days.

At an elevation of 1,206 feet, Atchison County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°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
Atchison County, MO (Zone 5b) Moderate season
174 days
Last Spring Frost April 22
174 growing days
First Fall Frost October 13
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Atchison County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🌸 Bloom: Jun 3 – Sep 2
Recommended (50%) ✓ Fits season (34 days to spare)
Start indoors: Mar 11 Transplant: Apr 22 🌸 Bloom: Jun 10 – Sep 9
Safe Start (90%) ✓ Fits season (35 days to spare)
Start indoors: Mar 24 Transplant: May 5 🌸 Bloom: Jun 23 – 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 Atchison County

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

Soil pH

Your soil pH (5.3–6.8) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.0%). 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 174-day season

Sow every 5.7 weeks. Last sowing by Aug 04 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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 3.1" 0" ❄️ Dormant
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 4.4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.6" 0" ✅ Rainfall sufficient
Jul 2.2" 4.2" 0" ✅ Rainfall sufficient
Aug 2.2" 4.3" 0" ✅ Rainfall sufficient
Sep 2.2" 4.1" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 3.2" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Atchison 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 ~735 GDD — county provides 2,131 GDD Excellent fit

Calendula Planting Timeline — Atchison County, MO

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 – Mar 25
Transplant Outdoors April 22 Apr 22 – May 6
Direct Sow April 1 Apr 1 – Apr 22
Bloom June 10 Jun 10 – Sep 9

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 5b

📆 Growing Season

174 days in Atchison County

Growing Tips for Calendula in Atchison County

Direct sow Calendula outdoors after April 22 in Atchison 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 Atchison County, MO?

Atchison County is in Zone 5b with an average last frost of April 22. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Atchison County, MO?

Atchison County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 22 and first fall frost is October 13.

When should I plant Calendula in Atchison County County, ?

In Atchison County County, , plant Calendula after the last frost (around April 22) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Atchison County County, for Calendula?

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

Can Calendula grow in Atchison County County's climate?

Yes — Calendula grows well in Atchison County County's temperate climate. Atchison County County averages a 174-day frost-free season, with last frost around April 22 and first frost around October 13.

🌱

Your Atchison County Garden Planner — Free

A 22-page printable planner built for Atchison County (Zone 5b). 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 Atchison County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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