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When to plant Vinca (Annual) in Suwannee County, FL

In Suwannee County, Vinca (Annual) is a single-season spring crop — there's no second fall window. Plant February 11–February 25 for an 70–90-day harvest, finishing well before the November 26 first frost.

When to Plant Vinca (Annual) in Suwannee County, FL

Suwannee County, Florida Zone 9a July

Your July game plan for Suwannee County, Florida

Welcome to July in Zone 9a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 4
Avg. first frost November 26
Soil temp (4") 91°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Basket week: vinca (annual)

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

A few tasks this July that'll pay off in August
  • 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.

Suwannee County, Florida is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 26, giving you a growing season of approximately 267 days.

At an elevation of 383 feet, Suwannee County receives approximately 53.6 inches of rainfall annually with predominantly sand soil. Summer highs average 91°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
Suwannee County, FL (Zone 9a) Long season
267 days
Last Spring Frost March 4
267 growing days
First Fall Frost November 26

Suwannee County Soil Profile

Soil Type

Sand

Soil pH

5.1-6

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (39 days to spare)
Start indoors: Dec 11 Transplant: Jan 29 🌸 Bloom: Apr 9 – Oct 8
Recommended (50%) ✓ Fits season (36 days to spare)
Start indoors: Dec 24 Transplant: Feb 11 🌸 Bloom: Apr 22 – Oct 21
Safe Start (90%) ✓ Fits season (40 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 Suwannee County

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

Soil pH

Your soil pH (5.1–6.0) is more acidic than Vinca (Annual) prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is low (1.4%). 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 28 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/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 2.5" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 2.2" 3.2" 0" ✅ Rainfall sufficient
Apr 2.2" 2.6" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 8" 0" ✅ Rainfall sufficient
Jul 2.2" 7.8" 0" ✅ Rainfall sufficient
Aug 2.2" 7.3" 0" ✅ Rainfall sufficient
Sep 2.2" 7.1" 0" ✅ Rainfall sufficient
Oct 2.2" 4.1" 0" ✅ Rainfall sufficient
Nov 2.2" 2.3" 0" ✅ Rainfall sufficient
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Suwannee 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 ~1,460 GDD — county provides 4,872 GDD Excellent fit

Vinca (Annual) Planting Timeline — Suwannee County, FL

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors December 24 Dec 24 – Jan 7
Transplant Outdoors February 11 Feb 11 – Feb 25
Bloom April 22 Apr 22 – Oct 21

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 Suwannee County

Growing Tips for Vinca (Annual) in Suwannee County

Direct sow Vinca (Annual) outdoors after March 04 in Suwannee County when soil has warmed and frost danger has passed.

Sandy soil in Suwannee 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 Suwannee County, FL?

Suwannee County is in Zone 9a with an average last frost of March 4. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Suwannee County, FL?

Suwannee County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 26.

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

In Suwannee County, FL, plant Vinca (Annual) after the last frost (around March 4) and before the first frost (around November 26). Best results when soil holds above 50°F.

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

Suwannee 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 Suwannee County's climate?

Yes — Vinca (Annual) grows well in Suwannee County's temperate climate. Suwannee County averages a 267-day frost-free season, with last frost around March 4 and first frost around November 26.

🌱

Your Suwannee County Garden Planner — Free

A 22-page printable planner built for Suwannee 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 Suwannee County, FL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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