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When to plant Vinca (Annual) in Marshall County, MS

Plant Vinca (Annual) in Marshall County during the brief March 27–April 10 window. With 218 frost-free days, fall plantings can't mature before October 31.

When to Plant Vinca (Annual) in Marshall County, MS

Marshall County, Mississippi Zone 7b July

Your July gardening checklist

Your Marshall County, Mississippi garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost March 27
Avg. first frost October 31
Soil temp (4") 85°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. Basket week: vinca (annual)

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

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  • First harvests: vinca (annual)

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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.

Marshall County, Mississippi is in USDA Zone 7b. The average last spring frost is March 27 and the first fall frost is October 31, giving you a growing season of approximately 218 days.

At an elevation of 255 feet, Marshall County receives approximately 52.1 inches of rainfall annually with predominantly clay loam soil. Summer highs average 93°F, providing good warmth for Vinca (Annual) during the growing season. Clay soil retains moisture well for Vinca (Annual), but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Vinca (Annual) root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Marshall County, MS (Zone 7b) Long season
218 days
Last Spring Frost March 27
218 growing days
First Fall Frost October 31

Marshall County Soil Profile

Soil Type

Clay Loam

Soil pH

5.6-6.3

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Jan 9 Transplant: Mar 20 🌸 Bloom: May 29 – Oct 2
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Jan 16 Transplant: Mar 27 🌸 Bloom: Jun 5 – Oct 9
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Feb 4 Transplant: Apr 15 🌸 Bloom: Jun 24 – Oct 28

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 Marshall County

How your county's soil matches Vinca (Annual)'s growing requirements.

Soil pH

Your soil pH (5.6–6.3) is more acidic than Vinca (Annual) prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The clay loam soil in Marshall County is excellent for Vinca (Annual) — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Vinca (Annual).

How to Plant Vinca (Annual)

0.1"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Vinca (Annual)

3
successive plantings in your 218-day season

Sow every 8 weeks. Last sowing by Aug 02 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 4.5" 0" ❄️ Dormant
Feb 4.7" 0" ❄️ Dormant
Mar 2.2" 4.9" 0" ✅ Rainfall sufficient
Apr 2.2" 3.7" 0" ✅ Rainfall sufficient
May 2.2" 4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.1" 0" ✅ Rainfall sufficient
Jul 2.2" 5.1" 0" ✅ Rainfall sufficient
Aug 2.2" 5.6" 0" ✅ Rainfall sufficient
Sep 2.2" 4.4" 0" ✅ Rainfall sufficient
Oct 2.2" 3.1" 0" ✅ Rainfall sufficient
Nov 3.9" 0" ❄️ Dormant
Dec 4.2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Oct in Marshall 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) needs ~1,580 GDD — county provides 4,305 GDD Excellent fit

Vinca (Annual) Planting Timeline — Marshall County, MS

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors January 16 Jan 16 – Jan 30
Transplant Outdoors March 27 Mar 27 – Apr 10
Bloom June 5 Jun 5 – Oct 9

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February
March Transplant Outdoors
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: too_acidic

🗺️ USDA Zone

Zone 7b

📆 Growing Season

218 days in Marshall County

Growing Tips for Vinca (Annual) in Marshall County

Direct sow Vinca (Annual) outdoors after March 27 in Marshall County when soil has warmed and frost danger has passed.

With Marshall County's clay soil (34% clay), work in 3-4 inches of compost before planting Vinca (Annual). Avoid tilling when soil is wet to prevent compaction.

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 →

Frequently Asked Questions

When should I plant Vinca (Annual) in Marshall County, MS?

Marshall County is in Zone 7b with an average last frost of March 27. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Marshall County, MS?

Marshall County, Mississippi is in USDA Hardiness Zone 7b. The average last spring frost is March 27 and first fall frost is October 31.

When should I plant Vinca (Annual) in Marshall County, MS?

In Marshall County, MS, plant Vinca (Annual) after the last frost (around March 27) and before the first frost (around October 31). Best results when soil holds above 50°F.

What growing zone is Marshall County, MS for Vinca (Annual)?

Marshall County sits in USDA Zone 7b. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Marshall County's temperate climate. Marshall County averages a 218-day frost-free season, with last frost around March 27 and first frost around October 31.

🌱

Your Marshall County Garden Planner — Free

A 22-page printable planner built for Marshall County (Zone 7b). 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 Marshall County, MS. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.