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When to Plant Calendula in Washington County, TN

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.

Washington County, Tennessee is in USDA Zone 7b. The average last spring frost is April 15 and the first fall frost is October 22, giving you a growing season of approximately 190 days.

At an elevation of 2,969 feet, Washington County receives approximately 41.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Calendula during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Washington County, TN (Zone 7b) Moderate season
190 days
Last Spring Frost April 15
190 growing days
First Fall Frost October 22

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7.1

Drainage

Well Drained

Monthly Watering Guide for Calendula

Calendula needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Calendula Needs Rainfall You Supplement Action
Jan 3.4" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 3.8" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 2.8" 1.5" 💧 Light watering
Jun 4.3" 3.4" 0.9" 💧 Light watering
Jul 4.3" 4.3" 0" ✅ Rainfall sufficient
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 3.5" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Calendula Planting Timeline — Washington County, TN

Calendula Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow March 11 Mar 11 – Apr 1
Bloom June 3 Jun 3 – Sep 30
Fall Sowing August 27 Aug 27 – Sep 10

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7b

📆 Growing Season

190 days in Washington County

Growing Tips for Washington County

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 Washington County, TN?

Washington County is in Zone 7b 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 Washington County, TN?

Washington County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 15 and first fall frost is October 22.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington County (Zone 7b). 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 Washington County, TN. 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.