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When to plant Thyme in Des Moines County, IA

In Des Moines County, Thyme is a single-season spring crop — there's no second fall window. Plant April 24–May 8 for an 70–90-day harvest, finishing well before the October 16 first frost.

When to Plant Thyme in Des Moines County, IA

Thyme

Thyme is a low-growing perennial herb with tiny, aromatic leaves and a warm, earthy flavor. It is one of the most versatile culinary and medicinal herbs.

Des Moines County, Iowa is in USDA Zone 6a. The average last spring frost is April 17 and the first fall frost is October 16, giving you a growing season of approximately 182 days.

At an elevation of 606 feet, Des Moines County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Thyme during the growing season.

Des Moines County, IA (Zone 6a) Moderate season
182 days
Last Spring Frost April 17
182 growing days
First Fall Frost October 16

Des Moines County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Thyme Planting Timeline — Des Moines County, IA

Thyme Planting Calendar

Activity When Date Range
Transplant Outdoors April 24 Apr 24 – May 8
Harvest July 3 Jul 3 – Sep 4

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June
July Harvest
August Harvest
September Harvest
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

182 days in Des Moines County

Growing Tips for Des Moines County

Start from seed, cuttings, or divisions. Plant in well-drained, lean soil. Prune lightly after flowering. Replace plants every 3-4 years when they become woody.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Thyme in Des Moines County, IA?

Des Moines County is in Zone 6a with an average last frost of April 17. Plan your Thyme planting based on this frost date — see the calendar above for exact timing.

What planting zone is Des Moines County, IA?

Des Moines County, Iowa is in USDA Hardiness Zone 6a. The average last spring frost is April 17 and first fall frost is October 16.

When should I plant Thyme in Des Moines County, IA?

In Des Moines County, IA, plant Thyme after the last frost (around April 17) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Des Moines County, IA for Thyme?

Des Moines County sits in USDA Zone 6a. Thyme grows reliably in zones 4a through 9b, so it's a good fit here.

Can Thyme grow in Des Moines County's climate?

Yes — Thyme grows well in Des Moines County's temperate climate. Des Moines County averages a 182-day frost-free season, with last frost around April 17 and first frost around October 16.

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Your Des Moines County Garden Planner — Free

A 22-page printable planner built for Des Moines County (Zone 6a). 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 Des Moines County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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