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When to Plant Calendula in Uintah County, UT

Uintah County, Utah Zone 5b June

Your June game plan for Uintah County, Utah

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 10
Avg. first frost October 4
Soil temp (4") 51°F
Watering Critical
Pest pressure High
Daylight 14.8 hrs
  1. Sow calendula in trays indoors

    These need a head start before your last frost (May 10). Sow into cells now so you're ready to transplant in a few weeks.

  2. Pick calendula

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

July will be here before you know it — start on
  • 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.

Uintah County, Utah is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is October 4, giving you a growing season of approximately 147 days.

At an elevation of 6,372 feet, Uintah County receives approximately 12.7 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
Uintah County, UT (Zone 5b) Short season
147 days
Last Spring Frost May 10
147 growing days
First Fall Frost October 4

Uintah County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.8

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (7 days to spare)
Start indoors: Mar 21 Transplant: May 2 🌸 Bloom: Jun 20 – Sep 19
Recommended (50%) ✓ Fits season (7 days to spare)
Start indoors: Mar 29 Transplant: May 10 🌸 Bloom: Jun 28 – Sep 27
Safe Start (90%) ✓ Fits season (1 days to spare)
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 Uintah County

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

Soil pH

Your soil pH (6.6–7.8) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Uintah 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 (2.5%). 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 147-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
0.4″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 451 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 0.9" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 1.2" 0" ❄️ Dormant
May 2.2" 1.5" 0.7" 💧 Light watering
Jun 2.2" 0.9" 1.3" 🚿 Regular watering
Jul 2.2" 1.2" 1" 💧 Light watering
Aug 2.2" 1.2" 1" 💧 Light watering
Sep 2.2" 1.1" 1.1" 🚿 Regular watering
Oct 2.2" 1.2" 1" 💧 Light watering
Nov 0.9" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Uintah 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 2,021 GDD Excellent fit

Calendula Planting Timeline — Uintah County, UT

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 10 May 10 – May 24
Direct Sow April 19 Apr 19 – May 10
Bloom June 28 Jun 28 – Sep 27

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 · 1-2 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

147 days in Uintah County

Growing Tips for Calendula in Uintah County

Direct sow Calendula outdoors after May 10 in Uintah 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.

Uintah County receives only 13" 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 Uintah County, UT?

Uintah County is in Zone 5b with an average last frost of May 10. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Uintah County, UT?

Uintah County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is October 4.

🌱

Your Uintah County Garden Planner — Free

A 22-page printable planner built for Uintah 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 Uintah County, UT. 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.