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When to plant Vinca (Annual) in Trego County, KS

Trego County's 178-day season only supports one Vinca (Annual) planting per year. Sow between April 28 and May 12 for the best chance at full maturity before October 16.

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

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.

Trego County, Kansas is in USDA Zone 6a. The average last spring frost is April 21 and the first fall frost is October 16, giving you a growing season of approximately 178 days.

At an elevation of 618 feet, Trego County receives approximately 30.8 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Vinca (Annual) to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Trego County, KS (Zone 6a) Moderate season
178 days
Last Spring Frost April 21
178 growing days
First Fall Frost October 16

Trego County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.8

Drainage

Well Drained

Monthly Watering Guide for Vinca (Annual)

Vinca (Annual) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Vinca (Annual) Needs Rainfall You Supplement Action
Jan 0.9" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 4.6" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2" 2.3" 🚿 Regular watering
Nov 1.2" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Trego County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Vinca (Annual) Planting Timeline — Trego County, KS

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 10 Feb 10 – Feb 24
Transplant Outdoors April 28 Apr 28 – May 12
Bloom July 7 Jul 7 – Oct 13

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

178 days in Trego County

Growing Tips for Trego County

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 Trego County, KS?

Trego County is in Zone 6a with an average last frost of April 21. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Trego County, KS?

Trego County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 21 and first fall frost is October 16.

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

In Trego County, KS, plant Vinca (Annual) after the last frost (around April 21) and before the first frost (around October 16). Best results when soil holds above 50°F.

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

Trego 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 Trego County's climate?

Yes — Vinca (Annual) grows well in Trego County's temperate climate. Trego County averages a 178-day frost-free season, with last frost around April 21 and first frost around October 16.

🌱

Your Trego County Garden Planner — Free

A 22-page printable planner built for Trego 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 Trego County, KS. Local conditions may vary. Last updated: June 2026.

Sources & credits

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