When to plant Thyme in Dewitt,
Plant Thyme in Dewitt, between April 22 and May 6 — the only viable window. Zone 6a's short season (185 frost-free days) rules out a fall crop.
When to Plant Thyme in Dewitt, IL
What to do in June
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
Looking ahead to July
- 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.
Dewitt, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 17, giving you a growing season of approximately 185 days.
At an elevation of 801 feet, DeWitt County receives approximately 31.8 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.
Dewitt Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7
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 Dewitt
How your county's soil matches Thyme's growing requirements.
Soil pH
Your soil pH (6.1–7.0) is within Thyme's preferred range (6.0–8.0).
Soil Texture
The silt loam soil in DeWitt County is excellent for Thyme — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Thyme.
Organic Matter
Organic matter is excellent (5.0%) — Thyme will thrive.
How to Plant Thyme
Succession Planting Thyme
Sow every 8 weeks. Last sowing by Jul 19 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 | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 1.3" | 2.6" | 0" | ✅ Rainfall sufficient |
| May | 1.3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 1.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 1.3" | 3.2" | 0" | ✅ Rainfall sufficient |
| Aug | 1.3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Sep | 1.3" | 2.7" | 0" | ✅ Rainfall sufficient |
| Oct | 1.3" | 2.3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in DeWitt 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 — Dewitt, IL
Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Harvest | July 1 | Jul 1 – Sep 2 |
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 | — |
| 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: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
185 days in DeWitt County
Growing Tips for Thyme in Dewitt
Direct sow Thyme outdoors after April 15 in DeWitt 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
When should I plant Thyme in Dewitt, ?
In Dewitt, , plant Thyme after the last frost (around April 15) and before the first frost (around October 17). Best results when soil holds above 50°F.
What growing zone is Dewitt, for Thyme?
Dewitt sits in USDA Zone 6a. Thyme grows reliably in zones 4a through 9b, so it's a good fit here.
Can Thyme grow in Dewitt's climate?
Yes — Thyme grows well in Dewitt's temperate climate. Dewitt averages a 185-day frost-free season, with last frost around April 15 and first frost around October 17.
Your DeWitt County Garden Planner — Free
A 22-page printable planner built for DeWitt 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.