When to Plant Dill in Mercer County, PA
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.
Mercer County, Pennsylvania is in USDA Zone 5b. The average last spring frost is May 6 and the first fall frost is October 17, giving you a growing season of approximately 164 days.
At an elevation of 63 feet, Mercer County receives approximately 43.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Dill to ensure they mature before fall.
Mercer County Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.5
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.
Plant Water Budget
Dill Planting Timeline — Mercer County, PA
Dill Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 1 | Apr 1 – Apr 15 |
| Transplant Outdoors | April 29 | Apr 29 – May 13 |
| Direct Sow | April 22 | Apr 22 – May 13 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
| Harvest | June 10 | Jun 10 – Aug 12 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
40–60 days
Soil pH
5.5 – 7
USDA Zone
Zone 5b
Growing Season
164 days
Growing Tips for Mercer County
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
Level Up Your Garden
Dill in Other Locations
Frequently Asked Questions
When should I plant Dill in Mercer County, PA?
Mercer County is in Zone 5b with an average last frost of May 6. Plan your Dill planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mercer County, PA?
Mercer County, Pennsylvania is in USDA Hardiness Zone 5b. The average last spring frost is May 6 and first fall frost is October 17.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Mercer County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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