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When to plant Vinca (Annual) in Johnson County, MO

In Johnson County, Vinca (Annual) is a spring-only crop. Plant April 20–May 4 once soil hits 50°F.

When to Plant Vinca (Annual) in Johnson County, MO

Annual vinca (Catharanthus roseus), also called Madagascar periwinkle, is one of the most heat- and drought-tolerant bedding plants available. Glossy foliage stays attractive all season while cheerful pinwheel blooms continue without deadheading. A top performer in hot, humid Southern summers where impatiens and begonias struggle. Self-cleaning; requires little maintenance once established.

Johnson County, Missouri is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 23, giving you a growing season of approximately 193 days.

At an elevation of 1,218 feet, Johnson County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Vinca (Annual) during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Johnson County, MO (Zone 6b) Moderate season
193 days
Last Spring Frost April 13
193 growing days
First Fall Frost October 23

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Vinca (Annual) Planting Timeline — Johnson County, MO

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 2 Feb 2 – Feb 16
Transplant Outdoors April 20 Apr 20 – May 4
Bloom June 29 Jun 29 – Oct 12

Plant 0.1" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
April Transplant Outdoors
May Transplant Outdoors
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

193 days in Johnson County

Growing Tips for Johnson County

Start seeds indoors 10–12 weeks before last frost — germination requires warm soil (75–80°F) and darkness. Do not cover seeds deeply; they need just a light dusting. Direct sowing is rarely practiced due to slow seedling establishment. Transplant after soil warms and frost danger has passed. Excellent drought tolerance once established; avoid overwatering. Performs best in well-drained beds or containers in full sun.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Vinca (Annual) in Johnson County, MO?

Johnson County is in Zone 6b with an average last frost of April 13. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, MO?

Johnson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 23.

When should I plant Vinca (Annual) in Johnson County, MO?

In Johnson County, MO, plant Vinca (Annual) after the last frost (around April 13) and before the first frost (around October 23). Best results when soil holds above 50°F.

What growing zone is Johnson County, MO for Vinca (Annual)?

Johnson County sits in USDA Zone 6b. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

Can Vinca (Annual) grow in Johnson County's climate?

Yes — Vinca (Annual) grows well in Johnson County's temperate climate. Johnson County averages a 193-day frost-free season, with last frost around April 13 and first frost around October 23.

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A 22-page printable planner built for Johnson County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Johnson County, MO. Local conditions may vary. Last updated: July 2026.

Sources & credits

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