When to Plant Lemon Thyme in New Castle County, DE
This month in New Castle County, Delaware
Your New Castle County, Delaware garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
Looking ahead to June
- 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.
New Castle County, Delaware is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.
At an elevation of 415 feet, New Castle County receives approximately 38.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Lemon Thyme during the growing season.
New Castle County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-7.1
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 New Castle County
How your county's soil matches Lemon Thyme's growing requirements.
Soil pH
Your soil pH (5.2–7.1) overlaps with Lemon Thyme's range (6.0–8.0), though not a perfect match.
Soil Texture
The silt loam soil in New Castle County is excellent for Lemon Thyme — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Lemon Thyme.
How to Plant Lemon Thyme
Succession Planting Lemon Thyme
Sow every 8 weeks. Last sowing by Aug 02 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 | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.4" | 0" | ❄️ Dormant |
| Dec | — | 2.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in New Castle 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 — New Castle County, DE
Lemon Thyme Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Harvest | June 22 | Jun 22 – Aug 24 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | — |
| 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: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
208 days in New Castle County
Growing Tips for Lemon Thyme in New Castle County
Direct sow Lemon Thyme outdoors after April 06 in New Castle 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 New Castle County, DE?
New Castle County is in Zone 7b with an average last frost of April 6. Plan your Lemon Thyme planting based on this frost date — see the calendar above for exact timing.
What planting zone is New Castle County, DE?
New Castle County, Delaware is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 31.
Your New Castle County Garden Planner — Free
A 24-page printable planner built for New Castle County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.