When to plant Vinca (Annual) in Morgan County, MO
In Morgan County, Vinca (Annual) is a single-season spring crop — there's no second fall window. Plant April 16–April 30 for an 70–90-day harvest, finishing well before the October 27 first frost.
When to Plant Vinca (Annual) in Morgan County, MO
Your June planting checklist for Morgan County, Missouri
Each item below is timed to Morgan County, Missouri's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Time to start vinca (annual) inside
These need a head start before your last frost (April 9). Sow into cells now so you're ready to transplant in a few weeks.
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Collect vinca (annual) at their peak
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
July will be here before you know it — start on
- First harvests: vinca (annual)
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.
Morgan County, Missouri is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 27, giving you a growing season of approximately 201 days.
At an elevation of 624 feet, Morgan County receives approximately 36.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Vinca (Annual) during the growing season.
Morgan County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-7
Drainage
Well Drained
Vinca (Annual) 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 Morgan County
How your county's soil matches Vinca (Annual)'s growing requirements.
Soil pH
Your soil pH (5.5–7.0) overlaps with Vinca (Annual)'s range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Morgan County is excellent for Vinca (Annual) — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Vinca (Annual).
How to Plant Vinca (Annual)
Succession Planting Vinca (Annual)
Sow every 8 weeks. Last sowing by Jul 29 to harvest before frost.
Vinca (Annual) Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Vinca (Annual)
Vinca (Annual) 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 | Vinca (Annual) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Morgan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Vinca (Annual) 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.
Vinca (Annual) Planting Timeline — Morgan County, MO
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 29 | Jan 29 – Feb 12 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Bloom | June 25 | Jun 25 – Oct 8 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
201 days in Morgan County
Growing Tips for Vinca (Annual) in Morgan County
Direct sow Vinca (Annual) outdoors after April 09 in Morgan County when soil has warmed and frost danger has passed.
General growing tips
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 →
Vinca (Annual) in Other Locations
Frequently Asked Questions
When should I plant Vinca (Annual) in Morgan County, MO?
Morgan County is in Zone 6b with an average last frost of April 9. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Morgan County, MO?
Morgan County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 27.
When should I plant Vinca (Annual) in Morgan County, MO?
In Morgan County, MO, plant Vinca (Annual) after the last frost (around April 9) and before the first frost (around October 27). Best results when soil holds above 50°F.
What growing zone is Morgan County, MO for Vinca (Annual)?
Morgan 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 Morgan County's climate?
Yes — Vinca (Annual) grows well in Morgan County's temperate climate. Morgan County averages a 201-day frost-free season, with last frost around April 9 and first frost around October 27.
Your Morgan County Garden Planner — Free
A 22-page printable planner built for Morgan 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.