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When to Plant Cosmos in Jerauld County, SD

Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.

Jerauld County, South Dakota is in USDA Zone 5a. The average last spring frost is May 2 and the first fall frost is October 5, giving you a growing season of approximately 156 days.

At an elevation of 775 feet, Jerauld County receives approximately 20.2 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Cosmos to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Jerauld County, SD (Zone 5a) Moderate season
156 days
Last Spring Frost May 2
156 growing days
First Fall Frost October 5

Jerauld County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Cosmos Planting Timeline — Jerauld County, SD

Cosmos Planting Calendar

Activity When Date Range
Start Indoors April 4 Apr 4 – Apr 18
Transplant Outdoors May 9 May 9 – May 23
Direct Sow May 9 May 9 – May 30
Bloom July 18 Jul 18 – Oct 10

Plant 0.3" deep · 12" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

156 days in Jerauld County

Growing Tips for Jerauld County

Direct-sow after last frost; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cosmos in Jerauld County, SD?

Jerauld County is in Zone 5a with an average last frost of May 2. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jerauld County, SD?

Jerauld County, South Dakota is in USDA Hardiness Zone 5a. The average last spring frost is May 2 and first fall frost is October 5.

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Your Jerauld County Garden Planner — Free

A 22-page printable planner built for Jerauld 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 Jerauld County, SD. Local conditions may vary. Last updated: June 2026.

Sources & credits

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