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When to plant Vinca (Annual) in Pine County, MN

In Pine County, Vinca (Annual) is a single-season spring crop — there's no second fall window. Plant May 24–June 7 for an 70–90-day harvest, finishing well before the September 29 first frost.

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

Pine County, Minnesota Zone 4a July

July in the garden — Pine County, Minnesota

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

Avg. last frost May 10
Avg. first frost September 29
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Fire up the seed-starting tray: vinca (annual)

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

August will be here before you know it — start on
  • 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.

Pine County, Minnesota is in USDA Zone 4a. The average last spring frost is May 10 and the first fall frost is September 29, giving you a growing season of approximately 142 days.

At an elevation of 538 feet, Pine County receives approximately 33.4 inches of rainfall annually with predominantly silt 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
Pine County, MN (Zone 4a) Short season
142 days
Last Spring Frost May 10
142 growing days
First Fall Frost September 29

Pine County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 12 Transplant: May 14 🌸 Bloom: Jul 23 – Sep 24
Recommended (50%) ✗ May not fit
Start indoors: Feb 22 Transplant: May 24 🌸 Bloom: Aug 2 – Oct 4
Safe Start (90%) ✗ May not fit
Start indoors: Mar 5 Transplant: Jun 4 🌸 Bloom: Aug 13 – 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 Pine County

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

Soil pH

Your soil pH (6.0–7.3) overlaps with Vinca (Annual)'s range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — 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 142-day season

Sow every 8 weeks. Last sowing by Jul 01 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/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 1.4" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 3.3" 0" ❄️ Dormant
May 2.2" 3.6" 0" ✅ Rainfall sufficient
Jun 2.2" 4.4" 0" ✅ Rainfall sufficient
Jul 2.2" 3.8" 0" ✅ Rainfall sufficient
Aug 2.2" 3.1" 0" ✅ Rainfall sufficient
Sep 2.2" 3.5" 0" ✅ Rainfall sufficient
Oct 2.3" 0" ❄️ Dormant
Nov 2.1" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Pine 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 ~1,040 GDD — county provides 1,846 GDD Excellent fit

Vinca (Annual) Planting Timeline — Pine County, MN

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors February 22 Feb 22 – Mar 8
Transplant Outdoors May 24 May 24 – Jun 7
Bloom August 2 Aug 2 – Oct 4

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 4a

📆 Growing Season

142 days in Pine County

Growing Tips for Vinca (Annual) in Pine County

Direct sow Vinca (Annual) outdoors after May 10 in Pine 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 Pine County, MN?

Pine County is in Zone 4a with an average last frost of May 10. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Pine County, MN?

Pine County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 10 and first fall frost is September 29.

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

In Pine County, MN, plant Vinca (Annual) after the last frost (around May 10) and before the first frost (around September 29). Best results when soil holds above 50°F.

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

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

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

Yes — Vinca (Annual) grows well in Pine County's temperate climate. Pine County averages a 142-day frost-free season, with last frost around May 10 and first frost around September 29.

🌱

Your Pine County Garden Planner — Free

A 22-page printable planner built for Pine County (Zone 4a). 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 Pine County, MN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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