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When to plant Petunia in Pine County, MN

Pine County's short 142-day growing season means one Petunia planting between May 24 and June 7. No fall crop in Zone 4a.

When to Plant Petunia in Pine County, MN

Petunias (Petunia x hybrida) are warm-season tender annuals prized for their prolific, trumpet-shaped blooms in nearly every color. They perform from hanging baskets to garden borders and bloom continuously from late spring until frost, provided spent flowers are removed regularly.

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 Petunia to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Fragrant
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

Monthly Watering Guide for Petunia

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

Month Petunia 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 4.3" 3.6" 0.7" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.1" 1.2" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
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.

Petunia Planting Timeline — Pine County, MN

Petunia Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors May 24 May 24 – Jun 7
Bloom August 9 Aug 9 – Oct 11

· 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
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

Moderate — regular watering

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 4a

📆 Growing Season

142 days in Pine County

Growing Tips for Pine County

Start seeds indoors 8–10 weeks before last frost; seeds need light to germinate — press onto moist mix surface, do not cover. Transplant after last frost once nights stay above 50°F. Pinch back leggy plants mid-summer to encourage bushy re-bloom. Wave/spreading types tolerate light shade but bloom less. Feed every 2 weeks with balanced fertilizer once established.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Petunia in Pine County, MN?

Pine County is in Zone 4a with an average last frost of May 10. Plan your Petunia 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 Petunia in Pine County, MN?

In Pine County, MN, plant Petunia 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 Petunia?

Pine County sits in USDA Zone 4a. Petunia grows reliably in zones 2a through 11b, so it's a good fit here.

Can Petunia grow in Pine County's climate?

Yes — Petunia 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.

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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: June 2026.

Sources & credits

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