When to Plant Lemon Thyme in Jackson County, IA
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.
Jackson County, Iowa is in USDA Zone 5a. The average last spring frost is April 17 and the first fall frost is October 16, giving you a growing season of approximately 182 days.
At an elevation of 1,321 feet, Jackson County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Lemon Thyme during the growing season.
Jackson County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-6.9
Drainage
Well Drained
Plant 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 Jackson County
How your county's soil matches Lemon Thyme's growing requirements.
Soil pH
Your soil pH (6.2–6.9) is within Lemon Thyme's preferred range (6.0–8.0).
Soil Texture
The silt loam soil in Jackson County is excellent for Lemon Thyme — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Lemon Thyme will thrive.
How to Plant Lemon Thyme
Succession Planting Lemon Thyme
Sow every 8 weeks. Last sowing by Jul 18 to harvest before frost.
Plant 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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Jackson 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 — Jackson County, IA
Lemon Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Harvest | July 3 | Jul 3 – Sep 4 |
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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: ideal
🗺️ USDA Zone
Zone 5a
📆 Growing Season
182 days in Jackson County
Growing Tips for Lemon Thyme in Jackson County
Direct sow Lemon Thyme outdoors after April 17 in Jackson 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 Jackson County, IA?
Jackson County is in Zone 5a with an average last frost of April 17. Plan your Lemon Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jackson County, IA?
Jackson County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 17 and first fall frost is October 16.
Plan Your Garden with Confidence
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