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When to plant Vinca (Annual) in Bryan County County,

Bryan County County sits in cold Zone 9a. Plant Vinca (Annual) February 9–February 23 for the single annual harvest; the November 24 first frost closes the window.

When to Plant Vinca (Annual) in Bryan County, GA

Bryan County, Georgia Zone 9a June

Your June gardening checklist

A quick June briefing for Bryan County, Georgia gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 2
Avg. first frost November 24
Soil temp (4") 81°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. It's harvest week for vinca (annual)

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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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.

Bryan County, Georgia is in USDA Zone 9a. The average last spring frost is March 2 and the first fall frost is November 24, giving you a growing season of approximately 267 days.

At an elevation of 193 feet, Bryan County receives approximately 54 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 92°F, providing good warmth for Vinca (Annual) during the growing season. Sandy soil warms quickly in spring — great for early planting — but Vinca (Annual) will need more frequent watering and organic matter to retain nutrients. 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
Bryan County, GA (Zone 9a) Long season
267 days
Last Spring Frost March 2
267 growing days
First Fall Frost November 24

Bryan County Soil Profile

Soil Type

Sandy Loam

Soil pH

5-6

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (45 days to spare)
Start indoors: Dec 6 Transplant: Jan 24 🌸 Bloom: Apr 4 – Oct 3
Recommended (50%) ✓ Fits season (36 days to spare)
Start indoors: Dec 22 Transplant: Feb 9 🌸 Bloom: Apr 20 – Oct 19
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Jan 13 Transplant: Mar 3 🌸 Bloom: May 12 – Nov 10

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 Bryan County

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

Soil pH

Your soil pH (5.0–6.0) is more acidic than Vinca (Annual) prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Bryan County warms quickly in spring but drains fast. Vinca (Annual) will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Vinca (Annual) prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is low (1.8%). Add 2-3 inches of compost before planting Vinca (Annual).

How to Plant Vinca (Annual)

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

Succession Planting Vinca (Annual)

4
successive plantings in your 267-day season

Sow every 8 weeks. Last sowing by Aug 26 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/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 4.1" 0" ❄️ Dormant
Mar 2.2" 5.3" 0" ✅ Rainfall sufficient
Apr 2.2" 4.2" 0" ✅ Rainfall sufficient
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 4.4" 0" ✅ Rainfall sufficient
Jul 2.2" 4.9" 0" ✅ Rainfall sufficient
Aug 2.2" 5.9" 0" ✅ Rainfall sufficient
Sep 2.2" 4.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3.6" 0" ✅ Rainfall sufficient
Nov 2.2" 4" 0" ✅ Rainfall sufficient
Dec 4.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Bryan 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 ~1,520 GDD — county provides 5,073 GDD Excellent fit

Vinca (Annual) Planting Timeline — Bryan County, GA

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors December 22 Dec 22 – Jan 5
Transplant Outdoors February 9 Feb 9 – Feb 23
Bloom April 20 Apr 20 – Oct 19

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

Month-by-Month Timeline

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

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 9a

📆 Growing Season

267 days in Bryan County

Growing Tips for Vinca (Annual) in Bryan County

Direct sow Vinca (Annual) outdoors after March 02 in Bryan County when soil has warmed and frost danger has passed.

Sandy soil in Bryan County dries quickly — mulch Vinca (Annual) with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Bryan County, GA?

Bryan County is in Zone 9a with an average last frost of March 2. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bryan County, GA?

Bryan County, Georgia is in USDA Hardiness Zone 9a. The average last spring frost is March 2 and first fall frost is November 24.

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

In Bryan County County, , plant Vinca (Annual) after the last frost (around March 2) and before the first frost (around November 24). Best results when soil holds above 50°F.

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

Bryan County County sits in USDA Zone 9a. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Bryan County County's temperate climate. Bryan County County averages a 267-day frost-free season, with last frost around March 2 and first frost around November 24.

🌱

Your Bryan County Garden Planner — Free

A 22-page printable planner built for Bryan County (Zone 9a). 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 Bryan County, GA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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