When to plant Calendula in Clay County, MO
Clay County's spring Calendula window runs March 16 through April 6. time plantings around the expected last-frost window for best survival.
When to Plant Calendula in Clay County, MO
Clay County, Missouri gardeners: here's your June plan
June is a pivotal month for Clay County, Missouri gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Harvest calendula as they ripen
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
To set up a strong July, finish these tasks
- First harvests: calendula
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.
Clay County, Missouri is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.
At an elevation of 1,373 feet, Clay County receives approximately 33.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Calendula during the growing season.
Clay County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.8
Drainage
Well Drained
Calendula 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 Clay County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (5.3–6.8) overlaps with Calendula's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Clay County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Calendula.
How to Plant Calendula
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Aug 15 to harvest before frost.
Calendula Water Budget
Monthly Watering Guide for Calendula
Calendula 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 | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clay County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Calendula 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.
Calendula Planting Timeline — Clay County, MO
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 16 | Mar 16 – Apr 6 |
| Bloom | June 1 | Jun 1 – Aug 31 |
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 Direct Sow |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
194 days in Clay County
Growing Tips for Calendula in Clay County
Direct sow Calendula outdoors after April 13 in Clay County when soil has warmed and frost danger has passed.
Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
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 Clay County, MO?
Clay County is in Zone 6a 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 Clay County, MO?
Clay County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 24.
When should I plant Calendula in Clay County, MO?
In Clay County, MO, plant Calendula after the last frost (around April 13) and before the first frost (around October 24). Best results when soil holds above 50°F.
What growing zone is Clay County, MO for Calendula?
Clay County sits in USDA Zone 6a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Clay County's climate?
Yes — Calendula grows well in Clay County's temperate climate. Clay County averages a 194-day frost-free season, with last frost around April 13 and first frost around October 24.
Your Clay County Garden Planner — Free
A 22-page printable planner built for Clay County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.