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

Plant Vinca (Annual) in Hendricks County County during the brief April 23–May 7 window. With 186 frost-free days, fall plantings can't mature before October 19.

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

Hendricks County, Indiana Zone 6a June

June to-do list for Hendricks County, Indiana

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

Avg. last frost April 16
Avg. first frost October 19
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Get vinca (annual) seeds going inside

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

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.

Hendricks County, Indiana is in USDA Zone 6a. The average last spring frost is April 16 and the first fall frost is October 19, giving you a growing season of approximately 186 days.

At an elevation of 1,286 feet, Hendricks County receives approximately 32.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Vinca (Annual) during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Hendricks County, IN (Zone 6a) Moderate season
186 days
Last Spring Frost April 16
186 growing days
First Fall Frost October 19
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Hendricks County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Jan 30 Transplant: Apr 17 🌸 Bloom: Jun 26 – Oct 2
Recommended (50%) ✓ Fits season (11 days to spare)
Start indoors: Feb 5 Transplant: Apr 23 🌸 Bloom: Jul 2 – Oct 8
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Feb 21 Transplant: May 9 🌸 Bloom: Jul 18 – Oct 24

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 Hendricks County

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

Soil pH

Your soil pH (6.2–7.2) overlaps with Vinca (Annual)'s range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.2%) — 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 186-day season

Sow every 8 weeks. Last sowing by Jul 21 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 1.5" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 2.2" 3" 0" ✅ Rainfall sufficient
May 2.2" 3.6" 0" ✅ Rainfall sufficient
Jun 2.2" 3.8" 0" ✅ Rainfall sufficient
Jul 2.2" 3.6" 0" ✅ Rainfall sufficient
Aug 2.2" 3.6" 0" ✅ Rainfall sufficient
Sep 2.2" 3.1" 0" ✅ Rainfall sufficient
Oct 2.2" 2.3" 0" ✅ Rainfall sufficient
Nov 2.3" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Hendricks 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 ~1,280 GDD — county provides 2,976 GDD Excellent fit

Vinca (Annual) Planting Timeline — Hendricks County, IN

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors April 23 Apr 23 – May 7
Bloom July 2 Jul 2 – Oct 8

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
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: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

186 days in Hendricks County

Growing Tips for Vinca (Annual) in Hendricks County

Direct sow Vinca (Annual) outdoors after April 16 in Hendricks 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 Hendricks County, IN?

Hendricks County is in Zone 6a with an average last frost of April 16. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hendricks County, IN?

Hendricks County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 16 and first fall frost is October 19.

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

In Hendricks County County, , plant Vinca (Annual) after the last frost (around April 16) and before the first frost (around October 19). Best results when soil holds above 50°F.

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

Hendricks County County sits in USDA Zone 6a. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Hendricks County County's temperate climate. Hendricks County County averages a 186-day frost-free season, with last frost around April 16 and first frost around October 19.

🌱

Your Hendricks County Garden Planner — Free

A 22-page printable planner built for Hendricks County (Zone 6a). 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 Hendricks 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.