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When to plant Calendula in Orange County County,

In Zone 10b (Orange County County), direct-sow Calendula between November 28 and December 19 for spring, after the February 13 last-frost mark. A second sowing from September 4 to September 18 extends the harvest into fall.

When to Plant Calendula in Orange County, CA

Orange County, California Zone 10b June

Orange County, California gardeners: here's your June plan

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 February 13
Avg. first frost December 11
Soil temp (4") 86°F
Watering Critical
Pest pressure High
Daylight 14.2 hrs
  1. Survive, don't thrive

    June-August is endurance gardening. Keep okra, peppers, sweet potatoes, and southern peas alive. Harvest everything daily before the heat damages produce on the vine.

  2. Start fall tomato seeds indoors

    Yes, indoors — under lights or in AC. They'll be ready to transplant in August when temperatures briefly moderate.

  3. Add compost to empty beds

    Empty beds get a thick layer of compost + mulch to suppress weeds and feed the soil for fall planting.

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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.

Orange County, California is in USDA Zone 10b. The average last spring frost is February 13 and the first fall frost is December 11, giving you a growing season of approximately 301 days.

At an elevation of 405 feet, Orange County receives approximately 13.8 inches of rainfall annually with predominantly loam soil. Summer highs average 88°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
Orange County, CA (Zone 10b) Year-round
301 days
Last Spring Frost February 13
301 growing days
First Fall Frost December 11
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Orange County Soil Profile

Soil Type

Loam

Soil pH

5.7-7.6

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (209 days to spare)
Transplant: Dec 15 🌸 Bloom: Jan 26 – May 4
Recommended (50%) ✓ Fits season (210 days to spare)
Transplant: Dec 26 🌸 Bloom: Feb 6 – May 15
Safe Start (90%) ✓ Fits season (171 days to spare)
Transplant: Feb 12 🌸 Bloom: Mar 26 – Jul 2

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 Orange County

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

Soil pH

Your soil pH (5.7–7.6) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Calendula.

How to Plant Calendula

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

Fall planting: Sow 14 weeks before your first frost date for a fall harvest.

Succession Planting Calendula

7
successive plantings in your 301-day season

Sow every 5.7 weeks. Last sowing by Oct 02 to harvest before frost.

For a dedicated fall crop, sow by Sep 04.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
0.2″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 994 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — 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 2.4" 0" ❄️ Dormant
Feb 2.2" 2.6" 0" ✅ Rainfall sufficient
Mar 2.2" 2.2" 0" ✅ Rainfall sufficient
Apr 2.2" 1.1" 1.1" 🚿 Regular watering
May 2.2" 0.4" 1.8" 🚿 Regular watering
Jun 2.2" 0.1" 2.1" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.2" 2" 🚿 Regular watering
Oct 2.2" 0.7" 1.5" 🚿 Regular watering
Nov 2.2" 1.5" 0.7" 💧 Light watering
Dec 2.2" 2.7" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Orange 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 ~960 GDD — county provides 4,832 GDD Excellent fit

Calendula Planting Timeline — Orange County, CA

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors December 26 Dec 26 – Jan 9
Direct Sow November 28 Nov 28 – Dec 19
Bloom February 6 Feb 6 – May 15
Fall Sowing September 4 Sep 4 – Sep 18

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

Month-by-Month Timeline

MonthActivities
January Transplant Outdoors
February Bloom
March Bloom
April Bloom
May Bloom
June
July
August
September Fall Sowing
October
November Direct Sow
December Transplant Outdoors Direct Sow
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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: acceptable

🗺️ USDA Zone

Zone 10b

📆 Growing Season

301 days in Orange County

Growing Tips for Calendula in Orange County

Direct sow Calendula outdoors after February 13 in Orange 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.

Orange County receives only 14" 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 Orange County, CA?

Orange County is in Zone 10b with an average last frost of February 13. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Orange County, CA?

Orange County, California is in USDA Hardiness Zone 10b. The average last spring frost is February 13 and first fall frost is December 11.

When should I plant Calendula in Orange County County, ?

In Orange County County, , plant Calendula after the last frost (around February 13) and before the first frost (around December 11). Best results when soil holds above 50°F.

What growing zone is Orange County County, for Calendula?

Orange County County sits in USDA Zone 10b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Orange County County's climate?

Yes — Calendula grows well in Orange County County's temperate climate. Orange County County averages a 302-day frost-free season, with last frost around February 13 and first frost around December 11.

🌱

Your Orange County Garden Planner — Free

A 22-page printable planner built for Orange County (Zone 10b). 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 Orange County, CA. 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.