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

Bourbon County County's 200-day season only supports one Vinca (Annual) planting per year. Sow between April 8 and April 22 for the best chance at full maturity before October 25.

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

Bourbon County, Kansas Zone 7a June

June in Bourbon County, Kansas — your action list

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

Avg. last frost April 8
Avg. first frost October 25
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
  1. Get vinca (annual) seeds going inside

    These need a head start before your last frost (April 8). Sow into cells now so you're ready to transplant in a few weeks.

  2. It's harvest week for vinca (annual)

    If you can't use it all right away, check the food-preservation section of your planner.

July prep starts now
  • 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.

Bourbon County, Kansas is in USDA Zone 7a. The average last spring frost is April 8 and the first fall frost is October 25, giving you a growing season of approximately 200 days.

At an elevation of 438 feet, Bourbon County receives approximately 26 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
Bourbon County, KS (Zone 7a) Long season
200 days
Last Spring Frost April 8
200 growing days
First Fall Frost October 25
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Bourbon County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (18 days to spare)
Start indoors: Jan 22 Transplant: Apr 2 🌸 Bloom: Jun 11 – Oct 1
Recommended (50%) ✓ Fits season (18 days to spare)
Start indoors: Jan 28 Transplant: Apr 8 🌸 Bloom: Jun 17 – Oct 7
Safe Start (90%) ✓ Fits season (16 days to spare)
Start indoors: Feb 10 Transplant: Apr 21 🌸 Bloom: Jun 30 – Oct 20

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

Organic Matter

Organic matter is moderate (3.8%). 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 200-day season

Sow every 8 weeks. Last sowing by Jul 27 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

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 0.6" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 2.2" 2.7" 0" ✅ Rainfall sufficient
May 2.2" 4.2" 0" ✅ Rainfall sufficient
Jun 2.2" 3.8" 0" ✅ Rainfall sufficient
Jul 2.2" 3.2" 0" ✅ Rainfall sufficient
Aug 2.2" 3.3" 0" ✅ Rainfall sufficient
Sep 2.2" 2.4" 0" ✅ Rainfall sufficient
Oct 2.2" 1.8" 0.4" 💧 Light watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Bourbon 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 2,750 GDD Excellent fit

Vinca (Annual) Planting Timeline — Bourbon County, KS

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors January 28 Jan 28 – Feb 11
Transplant Outdoors April 8 Apr 8 – Apr 22
Bloom June 17 Jun 17 – Oct 7

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: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

200 days in Bourbon County

Growing Tips for Vinca (Annual) in Bourbon County

Direct sow Vinca (Annual) outdoors after April 08 in Bourbon 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 Bourbon County, KS?

Bourbon County is in Zone 7a with an average last frost of April 8. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bourbon County, KS?

Bourbon County, Kansas is in USDA Hardiness Zone 7a. The average last spring frost is April 8 and first fall frost is October 25.

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

In Bourbon County County, , plant Vinca (Annual) after the last frost (around April 8) and before the first frost (around October 25). Best results when soil holds above 50°F.

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

Bourbon 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 Bourbon County County's climate?

Yes — Vinca (Annual) grows well in Bourbon County County's temperate climate. Bourbon County County averages a 200-day frost-free season, with last frost around April 8 and first frost around October 25.

🌱

Your Bourbon County Garden Planner — Free

A 22-page printable planner built for Bourbon 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 Bourbon 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.