When to plant Thyme in Mitchell County, IA
In Mitchell County, Thyme is a single-season spring crop — there's no second fall window. Plant May 10–May 24 for an 70–90-day harvest, finishing well before the October 7 first frost.
When to Plant Thyme in Mitchell County, IA
Your June planting checklist for Mitchell County, Iowa
A quick June briefing for Mitchell County, Iowa gardeners — what's urgent, what's next, and what can wait.
July will be here before you know it — start on
- First harvests: 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.
Mitchell County, Iowa is in USDA Zone 5a. The average last spring frost is May 3 and the first fall frost is October 7, giving you a growing season of approximately 157 days.
At an elevation of 506 feet, Mitchell County receives approximately 36.1 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.
Mitchell County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.3
Drainage
Well Drained
Thyme Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Mitchell County
How your county's soil matches Thyme's growing requirements.
Soil pH
Your soil pH (5.9–7.3) overlaps with Thyme's range (6.0–8.0), though not a perfect match.
Soil Texture
The silt loam soil in Mitchell County is excellent for Thyme — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Thyme will thrive.
How to Plant Thyme
Succession Planting Thyme
Sow every 8 weeks. Last sowing by Jul 09 to harvest before frost.
Thyme Water Budget
Monthly Watering Guide for Thyme
Thyme needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.
| Month | Thyme Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | — | 3.3" | 0" | ❄️ Dormant |
| May | 1.3" | 4" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 2.9" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 2.4" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Mitchell County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Thyme Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Thyme Planting Timeline — Mitchell County, IA
Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 10 | May 10 – May 24 |
| Harvest | July 19 | Jul 19 – Sep 20 |
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
0.3"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
157 days in Mitchell County
Growing Tips for Thyme in Mitchell County
Direct sow Thyme outdoors after May 03 in Mitchell County when soil has warmed and frost danger has passed.
General growing tips
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 Mitchell County, IA?
Mitchell County is in Zone 5a with an average last frost of May 3. Plan your Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mitchell County, IA?
Mitchell County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 3 and first fall frost is October 7.
When should I plant Thyme in Mitchell County, IA?
In Mitchell County, IA, plant Thyme after the last frost (around May 3) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Mitchell County, IA for Thyme?
Mitchell County sits in USDA Zone 5a. Thyme grows reliably in zones 4a through 9b, so it's a good fit here.
Can Thyme grow in Mitchell County's climate?
Yes — Thyme grows well in Mitchell County's temperate climate. Mitchell County averages a 157-day frost-free season, with last frost around May 3 and first frost around October 7.
Your Mitchell County Garden Planner — Free
A 22-page printable planner built for Mitchell 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.