When to plant Thyme in Marion County, IA
Marion County's 159-day season only supports one Thyme planting per year. Sow between May 8 and May 22 for the best chance at full maturity before October 7.
When to Plant Thyme in Marion County, IA
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.
Marion County, Iowa is in USDA Zone 5b. The average last spring frost is May 1 and the first fall frost is October 7, giving you a growing season of approximately 159 days.
At an elevation of 971 feet, Marion County receives approximately 33.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Thyme to ensure they mature before fall.
Marion County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Thyme Planting Timeline — Marion County, IA
Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Harvest | July 17 | Jul 17 – Sep 18 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| 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 5b
📆 Growing Season
159 days in Marion County
Growing Tips for Marion 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 →
Thyme in Other Locations
Frequently Asked Questions
When should I plant Thyme in Marion County, IA?
Marion County is in Zone 5b with an average last frost of May 1. Plan your Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, IA?
Marion County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is May 1 and first fall frost is October 7.
When should I plant Thyme in Marion County, IA?
In Marion County, IA, plant Thyme after the last frost (around May 1) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Marion County, IA for Thyme?
Marion County sits in USDA Zone 5b. Thyme grows reliably in zones 4a through 9b, so it's a good fit here.
Can Thyme grow in Marion County's climate?
Yes — Thyme grows well in Marion County's temperate climate. Marion County averages a 159-day frost-free season, with last frost around May 1 and first frost around October 7.
Your Marion County Garden Planner — Free
A 22-page printable planner built for Marion County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.