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When to Plant Calendula in Yamhill County, OR

Yamhill County, Oregon Zone 8b June

Top priorities for Yamhill County, Oregon gardeners in June

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

Avg. last frost April 15
Avg. first frost October 27
Soil temp (4") 80°F
Watering High
Pest pressure High
Daylight 15.4 hrs
  1. Harvest calendula as they ripen

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

July prep starts now
  • 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.

Yamhill County, Oregon is in USDA Zone 8b. The average last spring frost is April 15 and the first fall frost is October 27, giving you a growing season of approximately 195 days.

At an elevation of 476 feet, Yamhill County receives approximately 54.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Calendula during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Calendula root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Yamhill County, OR (Zone 8b) Moderate season
195 days
Last Spring Frost April 15
195 growing days
First Fall Frost October 27

Yamhill County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Calendula Planting Risk Windows

Early Start (70% safe) ✓ Fits season (18 days to spare)
Transplant: Mar 18 🌸 Bloom: May 6 – Sep 30
Recommended (50%) ✓ Fits season (20 days to spare)
Transplant: Mar 25 🌸 Bloom: May 13 – Oct 7
Safe Start (90%) ✓ Fits season (21 days to spare)
Transplant: Apr 17 🌸 Bloom: Jun 5 – Oct 30

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 Yamhill County

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

Soil pH

Your soil pH (5.4–6.2) overlaps with Calendula's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Calendula.

Organic Matter

Organic matter is excellent (4.3%) — Calendula will thrive.

How to Plant Calendula

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Calendula

4
successive plantings in your 195-day season

Sow every 5.7 weeks. Last sowing by Aug 18 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Calendula Water Budget

Plant needs
0.5″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 7.4" 0" ❄️ Dormant
Feb 6.4" 0" ❄️ Dormant
Mar 5.1" 0" ❄️ Dormant
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 2.8" 0" ✅ Rainfall sufficient
Jun 2.2" 2.1" 0.1" 💧 Light watering
Jul 2.2" 0.9" 1.3" 🚿 Regular watering
Aug 2.2" 1" 1.2" 🚿 Regular watering
Sep 2.2" 2.4" 0" ✅ Rainfall sufficient
Oct 2.2" 4.8" 0" ✅ Rainfall sufficient
Nov 9.3" 0" ❄️ Dormant
Dec 8.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Yamhill 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 ~1,050 GDD — county provides 3,412 GDD Excellent fit

Calendula Planting Timeline — Yamhill County, OR

Calendula Planting Calendar

Activity When Date Range
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow February 25 Feb 25 – Mar 18
Bloom May 13 May 13 – Oct 7
Fall Sowing August 18 Aug 18 – Sep 1

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

Month-by-Month Timeline

MonthActivities
January
February Direct Sow
March Transplant Outdoors Direct Sow
April Transplant Outdoors
May Bloom
June Bloom
July Bloom
August Fall Sowing Bloom
September Fall Sowing 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 8b

📆 Growing Season

195 days in Yamhill County

Growing Tips for Calendula in Yamhill County

Direct sow Calendula outdoors after April 15 in Yamhill 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 Yamhill County, OR?

Yamhill County is in Zone 8b with an average last frost of April 15. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Yamhill County, OR?

Yamhill County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 15 and first fall frost is October 27.

🌱

Your Yamhill County Garden Planner — Free

A 22-page printable planner built for Yamhill County (Zone 8b). 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 Yamhill County, OR. 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.