When to plant Lemon Thyme in Marion County, IL
Marion County sits in cold Zone 6b. Plant Lemon Thyme April 17–May 1 for the single annual harvest; the October 19 first frost closes the window.
When to Plant Lemon Thyme in Marion County, IL
What to do in July
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Marion County, Illinois.
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.
Marion County, Illinois is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 19, giving you a growing season of approximately 192 days.
At an elevation of 964 feet, Marion County receives approximately 40.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Lemon Thyme during the growing season.
Marion County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7
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 Marion County
How your county's soil matches Lemon Thyme's growing requirements.
Soil pH
Your soil pH (6.1–7.0) is within Lemon Thyme's preferred range (6.0–8.0).
Soil Texture
The silt loam soil in Marion County is excellent for Lemon Thyme — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lemon Thyme.
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 21 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.1" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Marion 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 — Marion County, IL
Lemon Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Harvest | June 26 | Jun 26 – Aug 28 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| 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 6b
📆 Growing Season
192 days in Marion County
Growing Tips for Lemon Thyme in Marion County
Direct sow Lemon Thyme outdoors after April 10 in Marion 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 Marion County, IL?
Marion County is in Zone 6b with an average last frost of April 10. Plan your Lemon Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, IL?
Marion County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 19.
When should I plant Lemon Thyme in Marion County, IL?
In Marion County, IL, plant Lemon Thyme after the last frost (around April 10) and before the first frost (around October 19). Best results when soil holds above 50°F.
What growing zone is Marion County, IL for Lemon Thyme?
Marion County sits in USDA Zone 6b. Lemon Thyme grows reliably in zones 5a through 9b, so it's a good fit here.
Can Lemon Thyme grow in Marion County's climate?
Yes — Lemon Thyme grows well in Marion County's temperate climate. Marion County averages a 192-day frost-free season, with last frost around April 10 and first frost around October 19.
Your Marion County Garden Planner — Free
A 22-page printable planner built for Marion County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.