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When to Plant Calendula in Gregory County, SD

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.

Gregory County, South Dakota is in USDA Zone 5a. The average last spring frost is May 10 and the first fall frost is October 6, giving you a growing season of approximately 149 days.

At an elevation of 668 feet, Gregory County receives approximately 34.5 inches of rainfall annually with predominantly loam soil. Summer highs average 82°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
Gregory County, SD (Zone 5a) Short season
149 days
Last Spring Frost May 10
149 growing days
First Fall Frost October 6

Gregory County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Calendula Planting Timeline — Gregory County, SD

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 20

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

Low — drought tolerant

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

149 days in Gregory County

Growing Tips for Gregory 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 Gregory County, SD?

Gregory County is in Zone 5a 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 Gregory County, SD?

Gregory County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 10 and first fall frost is October 6.

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Your Gregory County Garden Planner — Free

A 22-page printable planner built for Gregory County (Zone 5a). 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 Gregory County, SD. Local conditions may vary. Last updated: June 2026.

Sources & credits

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