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When to plant Calendula in Elbert County County,

Elbert County County sits in cold Zone 5b. Plant Calendula April 21–May 12 for the single annual harvest; the October 3 first frost closes the window.

When to Plant Calendula in Elbert County, CO

Elbert County, Colorado Zone 5b June

June in Elbert County, Colorado — your action list

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

Avg. last frost May 12
Avg. first frost October 3
Soil temp (4") 54°F
Watering High
Pest pressure High
Daylight 14.7 hrs
  1. Time to start calendula inside

    These need a head start before your last frost (May 12). Sow into cells now so you're ready to transplant in a few weeks.

  2. Pick calendula

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

Looking ahead to 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.

Elbert County, Colorado is in USDA Zone 5b. The average last spring frost is May 12 and the first fall frost is October 3, giving you a growing season of approximately 144 days.

At an elevation of 5,587 feet, Elbert County receives approximately 22.1 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Calendula during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Elbert County, CO (Zone 5b) Short season
144 days
Last Spring Frost May 12
144 growing days
First Fall Frost October 3

Elbert County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.7

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (3 days to spare)
Start indoors: Mar 22 Transplant: May 3 🌸 Bloom: Jun 21 – Sep 20
Recommended (50%) ✓ Fits season (4 days to spare)
Start indoors: Mar 31 Transplant: May 12 🌸 Bloom: Jun 30 – Sep 29
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Apr 16 Transplant: May 28 🌸 Bloom: Jul 16 – Oct 15

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 Elbert County

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

Soil pH

Your soil pH (6.2–7.7) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Calendula.

Organic Matter

Organic matter is moderate (2.8%). 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 144-day season

Sow every 5.7 weeks. Last sowing by Jul 25 to harvest before frost.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 8 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 1.4" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 2.2" 0" ❄️ Dormant
May 2.2" 2.4" 0" ✅ Rainfall sufficient
Jun 2.2" 1.7" 0.5" 💧 Light watering
Jul 2.2" 1.9" 0.3" 💧 Light watering
Aug 2.2" 2.3" 0" ✅ Rainfall sufficient
Sep 2.2" 2" 0.2" 💧 Light watering
Oct 2.2" 1.9" 0.3" 💧 Light watering
Nov 1.8" 0" ❄️ Dormant
Dec 1.4" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Elbert 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 ~915 GDD — county provides 2,196 GDD Excellent fit

Calendula Planting Timeline — Elbert County, CO

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 – Apr 14
Transplant Outdoors May 12 May 12 – May 26
Direct Sow April 21 Apr 21 – May 12
Bloom June 30 Jun 30 – Sep 29

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
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: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

144 days in Elbert County

Growing Tips for Calendula in Elbert County

Direct sow Calendula outdoors after May 12 in Elbert 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.

Elbert County receives only 22" 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 Elbert County, CO?

Elbert County is in Zone 5b with an average last frost of May 12. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Elbert County, CO?

Elbert County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 12 and first fall frost is October 3.

When should I plant Calendula in Elbert County County, ?

In Elbert County County, , plant Calendula after the last frost (around May 12) and before the first frost (around October 3). Best results when soil holds above 50°F.

What growing zone is Elbert County County, for Calendula?

Elbert 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 Elbert County County's climate?

Yes — Calendula grows well in Elbert County County's temperate climate. Elbert County County averages a 144-day frost-free season, with last frost around May 12 and first frost around October 3.

🌱

Your Elbert County Garden Planner — Free

A 22-page printable planner built for Elbert 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 Elbert County, CO. 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.