When to plant Calendula in Harrison County, MO
Harrison County gardeners should plant Calendula between March 29 and April 19 in spring. With Harrison County's Zone 5b climate (last frost April 19), Calendula needs 50–70 days to mature — plant by August 6 for a full harvest.
When to Plant Calendula in Harrison County, MO
Top priorities for Harrison County, Missouri gardeners in July
July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Harrison County, Missouri.
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Pick calendula
If you can't use it all right away, check the food-preservation section of your planner.
August prep starts now
- 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.
Harrison County, Missouri is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.
At an elevation of 1,349 feet, Harrison County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Calendula to ensure they mature before fall.
Harrison County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.9
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 Harrison County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (5.6–6.9) is within Calendula's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Harrison County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Calendula.
How to Plant Calendula
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Aug 06 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Harrison 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 — Harrison County, MO
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 8 | Mar 8 – Mar 22 |
| Transplant Outdoors | April 19 | Apr 19 – May 3 |
| Direct Sow | March 29 | Mar 29 – Apr 19 |
| Bloom | June 7 | Jun 7 – Sep 6 |
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 | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| 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: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
179 days in Harrison County
Growing Tips for Calendula in Harrison County
Direct sow Calendula outdoors after April 19 in Harrison 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 Harrison County, MO?
Harrison County is in Zone 5b with an average last frost of April 19. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harrison County, MO?
Harrison County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 15.
When should I plant Calendula in Harrison County, MO?
In Harrison County, MO, plant Calendula after the last frost (around April 19) and before the first frost (around October 15). Best results when soil holds above 50°F.
What growing zone is Harrison County, MO for Calendula?
Harrison County sits in USDA Zone 5b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Harrison County's climate?
Yes — Calendula grows well in Harrison County's temperate climate. Harrison County averages a 179-day frost-free season, with last frost around April 19 and first frost around October 15.
Your Harrison County Garden Planner — Free
A 22-page printable planner built for Harrison County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.