When to plant Calendula in Union County, KY
Union County gardeners should plant Calendula between March 2 and March 23 in spring. With Union County's Zone 7a climate (last frost April 6), Calendula needs 50–70 days to mature — plant by August 22 for a full harvest. A second sowing from September 5 to September 19 extends the harvest into fall.
When to Plant Calendula in Union 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.
Union County, Kentucky is in USDA Zone 7a. 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 1,482 feet, Union County receives approximately 48.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Calendula during the growing season.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.6
Drainage
Well Drained
Monthly Watering Guide for Calendula
Calendula needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.1" | 0" | ❄️ Dormant |
| Feb | — | 3.5" | 0" | ❄️ Dormant |
| Mar | — | 4.6" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4" | 0.3" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 5.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Oct | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Nov | — | 3.7" | 0" | ❄️ Dormant |
| Dec | — | 3.9" | 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.
Calendula Planting Timeline — Union County, KY
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 2 | Mar 2 – Mar 23 |
| Bloom | May 25 | May 25 – Sep 7 |
| Fall Sowing | September 5 | Sep 5 – Sep 19 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | 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
208 days in Union County
Growing Tips for Union 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 Union County, KY?
Union County is in Zone 7a with an average last frost of April 6. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, KY?
Union County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 6 and first fall frost is October 31.
When should I plant Calendula in Union County, KY?
In Union County, KY, plant Calendula after the last frost (around April 6) and before the first frost (around October 31). Best results when soil holds above 50°F.
What growing zone is Union County, KY for Calendula?
Union 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 Union County's climate?
Yes — Calendula grows well in Union County's temperate climate. Union County averages a 208-day frost-free season, with last frost around April 6 and first frost around October 31.
Your Union County Garden Planner — Free
A 22-page printable planner built for Union 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.