Blog

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

Plant Vinca (Annual) in Mower County County during the brief May 12–May 26 window. With 162 frost-free days, fall plantings can't mature before October 7.

When to Plant Vinca (Annual) in Mower County, MN

Mower County, Minnesota Zone 4b June

June to-do list for Mower County, Minnesota

Here's what deserves your attention in Mower County, Minnesota this month. Everything below is tailored to Zone 4b and timed around your local frost dates.

Avg. last frost April 28
Avg. first frost October 7
Soil temp (4") 64°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
Looking ahead to July
  • Starting indoors: vinca (annual)
  • First harvests: vinca (annual)

Instant PDF download. No spam, unsubscribe any time.

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.

Mower County, Minnesota is in USDA Zone 4b. The average last spring frost is April 28 and the first fall frost is October 7, giving you a growing season of approximately 162 days.

At an elevation of 577 feet, Mower County receives approximately 33 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Vinca (Annual) to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Mower County, MN (Zone 4b) Moderate season
162 days
Last Spring Frost April 28
162 growing days
First Fall Frost October 7

Mower County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.7

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Feb 6 Transplant: May 8 🌸 Bloom: Jul 17 – Sep 25
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Feb 10 Transplant: May 12 🌸 Bloom: Jul 21 – Sep 29
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Feb 26 Transplant: May 28 🌸 Bloom: Aug 6 – Oct 15

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 Mower County

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

Soil pH

Your soil pH (6.3–6.7) is within Vinca (Annual)'s preferred range (6.0–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.6%) — Vinca (Annual) will thrive.

How to Plant Vinca (Annual)

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

Succession Planting Vinca (Annual)

2
successive plantings in your 162-day season

Sow every 8 weeks. Last sowing by Jul 09 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 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.2" 3.7" 0" ✅ Rainfall sufficient
May 2.2" 3.4" 0" ✅ Rainfall sufficient
Jun 2.2" 3.9" 0" ✅ Rainfall sufficient
Jul 2.2" 3.3" 0" ✅ Rainfall sufficient
Aug 2.2" 3.6" 0" ✅ Rainfall sufficient
Sep 2.2" 2.8" 0" ✅ Rainfall sufficient
Oct 2.2" 2.4" 0" ✅ Rainfall sufficient
Nov 2.5" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Mower 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 ~920 GDD — county provides 1,863 GDD Excellent fit

Vinca (Annual) Planting Timeline — Mower County, MN

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 10 Feb 10 – Feb 24
Transplant Outdoors May 12 May 12 – May 26
Bloom July 21 Jul 21 – Sep 29

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

Month-by-Month Timeline

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

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 4b

📆 Growing Season

162 days in Mower County

Growing Tips for Vinca (Annual) in Mower County

Direct sow Vinca (Annual) outdoors after April 28 in Mower 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 Mower County, MN?

Mower County is in Zone 4b with an average last frost of April 28. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mower County, MN?

Mower County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is April 28 and first fall frost is October 7.

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

In Mower County County, , plant Vinca (Annual) after the last frost (around April 28) and before the first frost (around October 7). Best results when soil holds above 50°F.

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

Mower County County sits in USDA Zone 4b. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.

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

Yes — Vinca (Annual) grows well in Mower County County's temperate climate. Mower County County averages a 162-day frost-free season, with last frost around April 28 and first frost around October 7.

🌱

Your Mower County Garden Planner — Free

A 22-page printable planner built for Mower County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Mower County, MN. 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.