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

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

When to Plant Vinca (Annual) in Sumner County, KS

Sumner County, Kansas Zone 7a June

Your June planting checklist for Sumner County, Kansas

Your Sumner County, Kansas 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 11
Avg. first frost October 26
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. Get vinca (annual) seeds going inside

    Label every cell. You will absolutely forget which is which otherwise.

  2. Collect vinca (annual) at their peak

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

To set up a strong July, finish these tasks
  • 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.

Sumner County, Kansas is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 26, giving you a growing season of approximately 198 days.

At an elevation of 637 feet, Sumner County receives approximately 29 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Vinca (Annual) during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Sumner County, KS (Zone 7a) Moderate season
198 days
Last Spring Frost April 11
198 growing days
First Fall Frost October 26
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Sumner County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (17 days to spare)
Start indoors: Jan 25 Transplant: Apr 5 🌸 Bloom: Jun 14 – Oct 4
Recommended (50%) ✓ Fits season (16 days to spare)
Start indoors: Jan 31 Transplant: Apr 11 🌸 Bloom: Jun 20 – Oct 10
Safe Start (90%) ✓ Fits season (19 days to spare)
Start indoors: Feb 14 Transplant: Apr 25 🌸 Bloom: Jul 4 – 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 Sumner County

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

Soil pH

Your soil pH (6.4–7.8) is more alkaline than Vinca (Annual) prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Vinca (Annual).

How to Plant Vinca (Annual)

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

Succession Planting Vinca (Annual)

3
successive plantings in your 198-day season

Sow every 8 weeks. Last sowing by Jul 28 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/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 0.7" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 2.2" 3" 0" ✅ Rainfall sufficient
May 2.2" 4.4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.2" 0" ✅ Rainfall sufficient
Jul 2.2" 3.4" 0" ✅ Rainfall sufficient
Aug 2.2" 4" 0" ✅ Rainfall sufficient
Sep 2.2" 3" 0" ✅ Rainfall sufficient
Oct 2.2" 1.7" 0.5" 💧 Light watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Sumner 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 ~1,100 GDD — county provides 2,722 GDD Excellent fit

Vinca (Annual) Planting Timeline — Sumner County, KS

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors January 31 Jan 31 – Feb 14
Transplant Outdoors April 11 Apr 11 – Apr 25
Bloom June 20 Jun 20 – Oct 10

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March
April Transplant Outdoors
May
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: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

198 days in Sumner County

Growing Tips for Vinca (Annual) in Sumner County

Direct sow Vinca (Annual) outdoors after April 11 in Sumner 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 Sumner County, KS?

Sumner County is in Zone 7a with an average last frost of April 11. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sumner County, KS?

Sumner County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 26.

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

In Sumner County County, , plant Vinca (Annual) after the last frost (around April 11) and before the first frost (around October 26). Best results when soil holds above 50°F.

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

Sumner County County sits in USDA Zone 7a. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Sumner County County's temperate climate. Sumner County County averages a 198-day frost-free season, with last frost around April 11 and first frost around October 26.

🌱

Your Sumner County Garden Planner — Free

A 22-page printable planner built for Sumner County (Zone 7a). 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 Sumner County, KS. 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.