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When to plant Calendula in Alpine County County,

In Alpine County County, Calendula is a single-season spring crop — there's no second fall window. Plant April 21–May 12 for an 70-day harvest, finishing well before the October 3 first frost.

When to Plant Calendula in Alpine County, CA

Alpine County, California Zone 6b June

Top priorities for Alpine County, California gardeners in June

Here's what deserves your attention in Alpine County, California this month. Everything below is tailored to Zone 6b and timed around your local frost dates.

Avg. last frost May 19
Avg. first frost October 3
Soil temp (4") 69°F
Watering Critical
Pest pressure High
Daylight 14.7 hrs
  1. Begin indoor sowing: calendula

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

Coming up in July — start thinking about
  • 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.

Alpine County, California is in USDA Zone 6b. The average last spring frost is May 19 and the first fall frost is October 3, giving you a growing season of approximately 137 days.

At an elevation of 1,278 feet, Alpine County receives approximately 36.3 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Calendula to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Alpine County, CA (Zone 6b) Short season
137 days
Last Spring Frost May 19
137 growing days
First Fall Frost October 3

Alpine County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.3

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 22 Transplant: May 3 🌸 Bloom: Jun 21 – Sep 27
Recommended (50%) ✗ May not fit
Start indoors: Apr 7 Transplant: May 19 🌸 Bloom: Jul 7 – Oct 13
Safe Start (90%) ✗ May not fit
Start indoors: Apr 29 Transplant: Jun 10 🌸 Bloom: Jul 29 – Nov 4

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 Alpine County

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

Soil pH

Your soil pH (6.4–7.3) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.2%). 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 137-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
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 7.1" 0" ❄️ Dormant
Feb 8.7" 0" ❄️ Dormant
Mar 5.7" 0" ❄️ Dormant
Apr 2.7" 0" ❄️ Dormant
May 2.2" 1" 1.2" 🚿 Regular watering
Jun 2.2" 0.2" 2" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.3" 1.9" 🚿 Regular watering
Oct 2.2" 1.6" 0.6" 💧 Light watering
Nov 3.7" 0" ❄️ Dormant
Dec 5.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Alpine 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 ~780 GDD — county provides 1,781 GDD Excellent fit

Calendula Planting Timeline — Alpine County, CA

Calendula Planting Calendar

Activity When Date Range
Start Indoors April 7 Apr 7 – Apr 21
Transplant Outdoors May 19 May 19 – Jun 2
Direct Sow April 21 Apr 21 – May 12
Bloom July 7 Jul 7 – Oct 13

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Transplant Outdoors
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

137 days in Alpine County

Growing Tips for Calendula in Alpine County

Direct sow Calendula outdoors after May 19 in Alpine 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.

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 Alpine County, CA?

Alpine County is in Zone 6b with an average last frost of May 19. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Alpine County, CA?

Alpine County, California is in USDA Hardiness Zone 6b. The average last spring frost is May 19 and first fall frost is October 3.

When should I plant Calendula in Alpine County, ?

In Alpine County, , plant Calendula after the last frost (around May 19) and before the first frost (around October 3). Best results when soil holds above 50°F.

What growing zone is Alpine County, for Calendula?

Alpine County sits in USDA Zone 6b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.

Can Calendula grow in Alpine County's climate?

Yes — Calendula grows well in Alpine County's temperate climate. Alpine County averages a 137-day frost-free season, with last frost around May 19 and first frost around October 3.

🌱

Your Alpine County Garden Planner — Free

A 22-page printable planner built for Alpine County (Zone 6b). 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 Alpine 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.