When to Plant Dill in Union County, SC
May in Union County, South Carolina — your action list
Here's what deserves your attention in Union County, South Carolina this month. Everything below is tailored to Zone 8a and timed around your local frost dates.
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Get dill seeds going inside
These need a head start before your last frost (April 5). Sow into cells now so you're ready to transplant in a few weeks.
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Pick dill
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Get ahead of June
- First harvests: dill
Dill is a feathery annual herb with aromatic leaves and seeds. Its fine foliage and umbrella-shaped flower heads attract beneficial insects to the garden.
Union County, South Carolina is in USDA Zone 8a. The average last spring frost is April 5 and the first fall frost is October 31, giving you a growing season of approximately 209 days.
At an elevation of 478 feet, Union County receives approximately 53.3 inches of rainfall annually with predominantly clay loam soil. Summer highs average 91°F, providing good warmth for Dill during the growing season. Clay soil retains moisture well for Dill, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Dill root diseases.
Union County Soil Profile
Soil Type
Clay Loam
Soil pH
5.7-6.3
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 Union County
How your county's soil matches Dill's growing requirements.
Soil pH
Your soil pH (5.7–6.3) is within Dill's preferred range (5.5–7.0).
Soil Texture
The clay loam soil in Union County is excellent for Dill — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Dill.
How to Plant Dill
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Dill
Sow every 4.6 weeks. Last sowing by Sep 01 to harvest before frost.
For a dedicated fall crop, sow by Aug 22.
Plant Water Budget
Monthly Watering Guide for Dill
Dill 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 | Dill Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.1" | 0" | ❄️ Dormant |
| Feb | — | 3.9" | 0" | ❄️ Dormant |
| Mar | — | 4.5" | 0" | ❄️ Dormant |
| Apr | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.5" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 4.1" | 0" | ❄️ Dormant |
| Dec | — | 4.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Union County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Dill 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.
Dill Planting Timeline — Union County, SC
Dill Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 1 | Mar 1 – Mar 15 |
| Transplant Outdoors | March 29 | Mar 29 – Apr 12 |
| Direct Sow | March 22 | Mar 22 – Apr 12 |
| Harvest | May 10 | May 10 – Jul 12 |
| Fall Sowing | August 22 | Aug 22 – Sep 5 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 8a
📆 Growing Season
209 days in Union County
Growing Tips for Dill in Union County
Direct sow Dill outdoors after April 05 in Union County when soil has warmed and frost danger has passed.
With Union County's clay soil (27% clay), work in 3-4 inches of compost before planting Dill. Avoid tilling when soil is wet to prevent compaction.
Your generous 209.0-day season in Union County allows multiple plantings of Dill. Sow every 20.0 days for continuous harvest.
Common pests for Dill in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring as dill has a taproot and dislikes transplanting. Succession sow for continuous leaf harvest. Allow some plants to flower for seeds and to attract beneficial insects.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Dill in Other Locations
Frequently Asked Questions
When should I plant Dill in Union County, SC?
Union County is in Zone 8a with an average last frost of April 5. Plan your Dill planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, SC?
Union County, South Carolina is in USDA Hardiness Zone 8a. The average last spring frost is April 5 and first fall frost is October 31.
Your Union County Garden Planner — Free
A 24-page printable planner built for Union County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.