Blog

When to Plant Calendula in Clawson, UT

Emery County, Utah Zone 6a June

June to-do list for Emery County, Utah

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

Avg. last frost May 11
Avg. first frost October 4
Soil temp (4") 48°F
Watering Critical
Pest pressure High
Daylight 14.7 hrs
  1. Start calendula indoors

    Label every cell. You will absolutely forget which is which otherwise.

  2. Collect calendula at their peak

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

To set up a strong July, finish these tasks
  • First harvests: calendula

Instant PDF download. No spam, unsubscribe any time.

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.

Clawson, Utah is in USDA Zone 6a. The average last spring frost is May 11 and the first fall frost is October 4, giving you a growing season of approximately 146 days.

At an elevation of 7,259 feet, Emery County receives approximately 15.6 inches of rainfall annually with predominantly loam soil. Summer highs average 85°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
Clawson, UT (Zone 6a) Short season
146 days
Last Spring Frost May 11
146 growing days
First Fall Frost October 4

Clawson Soil Profile

Soil Type

Loam

Soil pH

6.3-7.9

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (9 days to spare)
Start indoors: Mar 20 Transplant: May 1 🌸 Bloom: Jun 19 – Sep 18
Recommended (50%) ✓ Fits season (6 days to spare)
Start indoors: Mar 30 Transplant: May 11 🌸 Bloom: Jun 29 – Sep 28
Safe Start (90%) ✗ May not fit
Start indoors: Apr 21 Transplant: Jun 2 🌸 Bloom: Jul 21 – Oct 20

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 Clawson

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

Soil pH

Your soil pH (6.3–7.9) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Emery 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 146-day season

Sow every 5.7 weeks. Last sowing by Jul 26 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 80 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" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 1.7" 0" ❄️ Dormant
May 2.2" 2" 0.2" 💧 Light watering
Jun 2.2" 1.1" 1.1" 🚿 Regular watering
Jul 2.2" 1.4" 0.8" 💧 Light watering
Aug 2.2" 1.6" 0.6" 💧 Light watering
Sep 2.2" 1.1" 1.1" 🚿 Regular watering
Oct 2.2" 1.5" 0.7" 💧 Light watering
Nov 0.9" 0" ❄️ Dormant
Dec 1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Emery 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 ~825 GDD — county provides 2,007 GDD Excellent fit

Calendula Planting Timeline — Clawson, UT

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 11 May 11 – May 25
Direct Sow April 13 Apr 13 – May 4
Bloom June 29 Jun 29 – Sep 28

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: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

146 days in Emery County

Growing Tips for Calendula in Clawson

Direct sow Calendula outdoors after May 11 in Emery 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.

Emery County receives only 16" 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 →

🌱

Your Emery County Garden Planner — Free

A 22-page printable planner built for Emery 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Emery County, UT. Local conditions may vary. Last updated: June 2026.