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

In Seminole County County, Vinca (Annual) is a single-season spring crop — there's no second fall window. Plant December 23–January 6 for an 90-day harvest, finishing well before the December 21 first frost.

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

Seminole County, Florida Zone 10a June

Top priorities for Seminole County, Florida gardeners in June

Here's what deserves your attention in Seminole County, Florida this month. Everything below is tailored to Zone 10a and timed around your local frost dates.

Avg. last frost February 3
Avg. first frost December 21
Soil temp (4") 87°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Start harvesting vinca (annual)

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

Before July arrives, get these ready
  • 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.

Seminole County, Florida is in USDA Zone 10a. The average last spring frost is February 3 and the first fall frost is December 21, giving you a growing season of approximately 321 days.

At an elevation of 260 feet, Seminole County receives approximately 53.9 inches of rainfall annually with predominantly sand soil. Summer highs average 95°F, so Vinca (Annual) may need afternoon shade and extra watering during peak heat. 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
Seminole County, FL (Zone 10a) Year-round
321 days
Last Spring Frost February 3
321 growing days
First Fall Frost December 21
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Seminole County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.9

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (80 days to spare)
Start indoors: Nov 10 Transplant: Dec 8 🌸 Bloom: Feb 16 – Sep 28
Recommended (50%) ✓ Fits season (69 days to spare)
Start indoors: Nov 25 Transplant: Dec 23 🌸 Bloom: Mar 3 – Oct 13
Safe Start (90%) ✓ Fits season (46 days to spare)
Start indoors: Dec 23 Transplant: Jan 20 🌸 Bloom: Mar 31 – 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 Seminole County

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

Soil pH

Your soil pH (5.2–5.9) is more acidic than Vinca (Annual) prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Vinca (Annual).

Organic Matter

Organic matter is low (1.5%). 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)

5
successive plantings in your 321-day season

Sow every 8 weeks. Last sowing by Sep 22 to harvest before frost.

Vinca (Annual) Water Budget

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

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 2.9" 0" ❄️ Dormant
Feb 2.2" 3" 0" ✅ Rainfall sufficient
Mar 2.2" 2.9" 0" ✅ Rainfall sufficient
Apr 2.2" 2.8" 0" ✅ Rainfall sufficient
May 2.2" 3.8" 0" ✅ Rainfall sufficient
Jun 2.2" 7.9" 0" ✅ Rainfall sufficient
Jul 2.2" 7.7" 0" ✅ Rainfall sufficient
Aug 2.2" 6.9" 0" ✅ Rainfall sufficient
Sep 2.2" 6.4" 0" ✅ Rainfall sufficient
Oct 2.2" 5.2" 0" ✅ Rainfall sufficient
Nov 2.2" 2.2" 0" ✅ Rainfall sufficient
Dec 2.2" 2.2" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Seminole 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 ~1,700 GDD — county provides 6,842 GDD Excellent fit

Vinca (Annual) Planting Timeline — Seminole County, FL

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors November 25 Nov 25 – Dec 9
Transplant Outdoors December 23 Dec 23 – Jan 6
Bloom March 3 Mar 3 – Oct 13

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

Month-by-Month Timeline

MonthActivities
January Transplant Outdoors
February
March Bloom
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November Start Indoors
December Start Indoors Transplant Outdoors
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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 10a

📆 Growing Season

321 days in Seminole County

Growing Tips for Vinca (Annual) in Seminole County

Direct sow Vinca (Annual) outdoors after February 03 in Seminole County when soil has warmed and frost danger has passed.

Sandy soil in Seminole 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 Seminole County, FL?

Seminole County is in Zone 10a with an average last frost of February 3. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Seminole County, FL?

Seminole County, Florida is in USDA Hardiness Zone 10a. The average last spring frost is February 3 and first fall frost is December 21.

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

In Seminole County County, , plant Vinca (Annual) after the last frost (around February 3) and before the first frost (around December 21). Best results when soil holds above 50°F.

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

Seminole County County sits in USDA Zone 10a. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Seminole County County's temperate climate. Seminole County County averages a 322-day frost-free season, with last frost around February 3 and first frost around December 21.

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Your Seminole County Garden Planner — Free

A 22-page printable planner built for Seminole County (Zone 10a). 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 Seminole County, FL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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