When to plant Calendula in Mercer County, KY
Mercer County gardeners should plant Calendula between March 9 and March 30 in spring. With Mercer County's Zone 7a climate (last frost April 13), Calendula needs 50–70 days to mature — plant by August 17 for a full harvest. A second sowing from August 31 to September 14 extends the harvest into fall.
When to Plant Calendula in Mercer County, KY
Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.
Mercer County, Kentucky is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 26, giving you a growing season of approximately 196 days.
At an elevation of 1,559 feet, Mercer County receives approximately 54.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Calendula during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Calendula root diseases.
Mercer County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Calendula Planting Timeline — Mercer County, KY
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | April 13 | Apr 13 – Apr 27 |
| Direct Sow | March 9 | Mar 9 – Mar 30 |
| Bloom | June 1 | Jun 1 – Sep 14 |
| Fall Sowing | August 31 | Aug 31 – Sep 14 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Fall Sowing Bloom |
| September | Fall Sowing Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
196 days in Mercer County
Growing Tips for Mercer County
Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Calendula in Other Locations
Frequently Asked Questions
When should I plant Calendula in Mercer County, KY?
Mercer County is in Zone 7a with an average last frost of April 13. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mercer County, KY?
Mercer County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 13 and first fall frost is October 26.
When should I plant Calendula in Mercer County, KY?
In Mercer County, KY, plant Calendula after the last frost (around April 13) and before the first frost (around October 26). Best results when soil holds above 50°F.
What growing zone is Mercer County, KY for Calendula?
Mercer County sits in USDA Zone 7a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Mercer County's climate?
Yes — Calendula grows well in Mercer County's temperate climate. Mercer County averages a 196-day frost-free season, with last frost around April 13 and first frost around October 26.
Your Mercer County Garden Planner — Free
A 22-page printable planner built for Mercer County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.