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When to plant Calendula in Crowley County, CO

In Zone 5b (Crowley County), direct-sow Calendula between April 5 and April 26 for spring, after the April 26 last-frost mark.

When to Plant Calendula in Crowley County, CO

Crowley County, Colorado Zone 5b June

What to do in June

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

Avg. last frost April 26
Avg. first frost October 9
Soil temp (4") 57°F
Watering High
Pest pressure High
Daylight 14.7 hrs
  1. Get calendula seeds going inside

    These need a head start before your last frost (April 26). Sow into cells now so you're ready to transplant in a few weeks.

  2. Bring in the calendula

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

A few tasks this June that'll pay off in 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.

Crowley County, Colorado is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 9, giving you a growing season of approximately 166 days.

At an elevation of 5,963 feet, Crowley County receives approximately 17.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Calendula during the growing season. With low rainfall, drip irrigation is essential for growing Calendula successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Crowley County, CO (Zone 5b) Moderate season
166 days
Last Spring Frost April 26
166 growing days
First Fall Frost October 9

Crowley County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.6

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (27 days to spare)
Start indoors: Mar 10 Transplant: Apr 21 🌸 Bloom: Jun 9 – Sep 8
Recommended (50%) ✓ Fits season (26 days to spare)
Start indoors: Mar 15 Transplant: Apr 26 🌸 Bloom: Jun 14 – Sep 13
Safe Start (90%) ✓ Fits season (24 days to spare)
Start indoors: Mar 31 Transplant: May 12 🌸 Bloom: Jun 30 – Sep 29

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 Crowley County

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

Soil pH

Your soil pH (6.6–7.6) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Calendula.

How to Plant Calendula

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

Succession Planting Calendula

3
successive plantings in your 166-day season

Sow every 5.7 weeks. Last sowing by Jul 31 to harvest before frost.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 88 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 1.3" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 2.2" 1.8" 0.4" 💧 Light watering
May 2.2" 2.2" 0" ✅ Rainfall sufficient
Jun 2.2" 1.3" 0.9" 💧 Light watering
Jul 2.2" 1.6" 0.6" 💧 Light watering
Aug 2.2" 2.1" 0.1" 💧 Light watering
Sep 2.2" 1.3" 0.9" 💧 Light watering
Oct 2.2" 1.4" 0.8" 💧 Light watering
Nov 1.2" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Crowley 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 2,905 GDD Excellent fit

Calendula Planting Timeline — Crowley County, CO

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 – Mar 29
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 5 Apr 5 – Apr 26
Bloom June 14 Jun 14 – Sep 13

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

166 days in Crowley County

Growing Tips for Calendula in Crowley County

Direct sow Calendula outdoors after April 26 in Crowley 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.

Crowley County receives only 18" of rain annually. Calendula needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Crowley County, CO?

Crowley County is in Zone 5b with an average last frost of April 26. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Crowley County, CO?

Crowley County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 9.

When should I plant Calendula in Crowley County, CO?

In Crowley County, CO, plant Calendula after the last frost (around April 26) and before the first frost (around October 9). Best results when soil holds above 50°F.

What growing zone is Crowley County, CO for Calendula?

Crowley 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 Crowley County's climate?

Yes — Calendula grows well in Crowley County's temperate climate. Crowley County averages a 166-day frost-free season, with last frost around April 26 and first frost around October 9.

🌱

Your Crowley County Garden Planner — Free

A 22-page printable planner built for Crowley 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 Crowley County, CO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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