When to plant Lemon Thyme in Cass County County,
Cass County County's 167-day season only supports one Lemon Thyme planting per year. Sow between May 2 and May 16 for the best chance at full maturity before October 9.
When to Plant Lemon Thyme in Cass County, IA
June to-do list for Cass County, Iowa
Here's what deserves your attention in Cass County, Iowa this month. Everything below is tailored to Zone 5b and timed around your local frost dates.
Get ahead of July
- First harvests: lemon thyme
Lemon thyme is a low-growing perennial herb with tiny, citrus-scented leaves. It combines the savory quality of thyme with a bright lemon flavor, excellent with fish and poultry.
Cass County, Iowa is in USDA Zone 5b. The average last spring frost is April 25 and the first fall frost is October 9, giving you a growing season of approximately 167 days.
At an elevation of 1,043 feet, Cass County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Lemon Thyme during the growing season.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-6.7
Drainage
Well Drained
Lemon 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 Cass County
How your county's soil matches Lemon Thyme's growing requirements.
Soil pH
Your soil pH (6.2–6.7) is within Lemon Thyme's preferred range (6.0–8.0).
Soil Texture
The silt loam soil in Cass County is excellent for Lemon Thyme — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.4%) — Lemon Thyme will thrive.
How to Plant Lemon Thyme
Succession Planting Lemon Thyme
Sow every 8 weeks. Last sowing by Jul 11 to harvest before frost.
Lemon Thyme Water Budget
Monthly Watering Guide for Lemon Thyme
Lemon Thyme needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Lemon Thyme Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lemon 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.
Lemon Thyme Planting Timeline — Cass County, IA
Lemon Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Harvest | July 11 | Jul 11 – Sep 12 |
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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
167 days in Cass County
Growing Tips for Lemon Thyme in Cass County
Direct sow Lemon Thyme outdoors after April 25 in Cass County when soil has warmed and frost danger has passed.
General growing tips
Start from cuttings or divisions. Plant in well-drained soil. Trim back after flowering. Use as a fragrant ground cover or edging plant along garden paths.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Lemon Thyme in Other Locations
Frequently Asked Questions
When should I plant Lemon Thyme in Cass County, IA?
Cass County is in Zone 5b with an average last frost of April 25. Plan your Lemon Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, IA?
Cass County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 25 and first fall frost is October 9.
When should I plant Lemon Thyme in Cass County County, ?
In Cass County County, , plant Lemon Thyme after the last frost (around April 25) and before the first frost (around October 9). Best results when soil holds above 50°F.
What growing zone is Cass County County, for Lemon Thyme?
Cass County County sits in USDA Zone 5b. Lemon Thyme grows reliably in zones 5a through 9b, so it's a good fit here.
Can Lemon Thyme grow in Cass County County's climate?
Yes — Lemon Thyme grows well in Cass County County's temperate climate. Cass County County averages a 167-day frost-free season, with last frost around April 25 and first frost around October 9.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass 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.