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

Plant Vinca (Annual) in Scott County County, between April 19 and May 3 — the only viable window. Zone 6b's short season (191 frost-free days) rules out a fall crop.

When to Plant Vinca (Annual) in Scott County, IN

Scott County, Indiana Zone 6b June

What to do in June

Your garden in Scott County, Indiana is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 12
Avg. first frost October 20
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Start vinca (annual) under lights

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Harvest vinca (annual) as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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.

Scott County, Indiana is in USDA Zone 6b. The average last spring frost is April 12 and the first fall frost is October 20, giving you a growing season of approximately 191 days.

At an elevation of 615 feet, Scott County receives approximately 40.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Vinca (Annual) during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Scott County, IN (Zone 6b) Moderate season
191 days
Last Spring Frost April 12
191 growing days
First Fall Frost October 20
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Scott County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.7

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Start indoors: Jan 28 Transplant: Apr 15 🌸 Bloom: Jun 24 – Oct 7
Recommended (50%) ✓ Fits season (9 days to spare)
Start indoors: Feb 1 Transplant: Apr 19 🌸 Bloom: Jun 28 – Oct 11
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Feb 19 Transplant: May 7 🌸 Bloom: Jul 16 – Oct 29

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 Scott County

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

Soil pH

Your soil pH (6.0–6.7) is within Vinca (Annual)'s preferred range (6.0–7.0).

Soil Texture

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

Drainage

Drainage is adequate for Vinca (Annual).

Organic Matter

Organic matter is excellent (4.5%) — Vinca (Annual) will thrive.

How to Plant Vinca (Annual)

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

Succession Planting Vinca (Annual)

3
successive plantings in your 191-day season

Sow every 8 weeks. Last sowing by Jul 22 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 1.7" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 2.2" 3.4" 0" ✅ Rainfall sufficient
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 5.7" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 4.9" 0" ✅ Rainfall sufficient
Sep 2.2" 3.9" 0" ✅ Rainfall sufficient
Oct 2.2" 3.4" 0" ✅ Rainfall sufficient
Nov 2.5" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Scott 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 ~1,160 GDD — county provides 2,769 GDD Excellent fit

Vinca (Annual) Planting Timeline — Scott County, IN

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 1 Feb 1 – Feb 15
Transplant Outdoors April 19 Apr 19 – May 3
Bloom June 28 Jun 28 – Oct 11

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 6b

📆 Growing Season

191 days in Scott County

Growing Tips for Vinca (Annual) in Scott County

Direct sow Vinca (Annual) outdoors after April 12 in Scott 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 →

Frequently Asked Questions

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

Scott County is in Zone 6b with an average last frost of April 12. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Scott County, IN?

Scott County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 12 and first fall frost is October 20.

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

In Scott County County, , plant Vinca (Annual) after the last frost (around April 12) and before the first frost (around October 20). Best results when soil holds above 50°F.

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

Scott County 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 Scott County County's climate?

Yes — Vinca (Annual) grows well in Scott County County's temperate climate. Scott County County averages a 191-day frost-free season, with last frost around April 12 and first frost around October 20.

🌱

Your Scott County Garden Planner — Free

A 22-page printable planner built for Scott 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.

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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 Scott County, IN. 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.