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When to plant Petunia in Stevens County, MN

In Stevens County, Petunia is a spring-only crop. Plant May 9–May 23 once soil hits 50°F.

When to Plant Petunia in Stevens County, MN

Stevens County, Minnesota Zone 4b June

Your June planting checklist for Stevens County, Minnesota

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

Avg. last frost May 2
Avg. first frost October 6
Soil temp (4") 64°F
Watering Low
Pest pressure High
Daylight 15.5 hrs
Coming up in July — start thinking about
  • Starting indoors: petunia
  • First harvests: petunia

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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.

Stevens County, Minnesota is in USDA Zone 4b. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.

At an elevation of 1,259 feet, Stevens County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Petunia to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Fragrant
Stevens County, MN (Zone 4b) Moderate season
157 days
Last Spring Frost May 2
157 growing days
First Fall Frost October 6

Stevens County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (3 days to spare)
Start indoors: Feb 22 Transplant: May 3 🌸 Bloom: Jul 12 – Sep 27
Recommended (50%) ✓ Fits season (3 days to spare)
Start indoors: Feb 28 Transplant: May 9 🌸 Bloom: Jul 18 – Oct 3
Safe Start (90%) ✓ Fits season (1 days to spare)
Start indoors: Mar 13 Transplant: May 22 🌸 Bloom: Jul 31 – Oct 16

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 Stevens County

How your county's soil matches Petunia's growing requirements.

Soil pH

Your soil pH (6.1–7.0) is within Petunia's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Stevens County is excellent for Petunia — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.0%) — Petunia will thrive.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

2
successive plantings in your 157-day season

Sow every 8 weeks. Last sowing by Jul 08 to harvest before frost.

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Only during dry spells
Season total 4 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.7" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.1" 0" ❄️ Dormant
May 4.3" 4.7" 0" ✅ Rainfall sufficient
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 3.6" 0.7" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

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

Petunia 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.

Petunia needs ~860 GDD — county provides 1,687 GDD Excellent fit

Petunia Planting Timeline — Stevens County, MN

Petunia Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors May 9 May 9 – May 23
Bloom July 18 Jul 18 – Oct 3

· 12" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

157 days in Stevens County

Growing Tips for Petunia in Stevens County

Direct sow Petunia outdoors after May 02 in Stevens County when soil has warmed and frost danger has passed.

Common pests for Petunia in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Stevens County, MN?

Stevens County is in Zone 4b with an average last frost of May 2. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Stevens County, MN?

Stevens County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 2 and first fall frost is October 6.

When should I plant Petunia in Stevens County, MN?

In Stevens County, MN, plant Petunia after the last frost (around May 2) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Stevens County, MN for Petunia?

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

Can Petunia grow in Stevens County's climate?

Yes — Petunia grows well in Stevens County's temperate climate. Stevens County averages a 157-day frost-free season, with last frost around May 2 and first frost around October 6.

🌱

Your Stevens County Garden Planner — Free

A 22-page printable planner built for Stevens 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.

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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 Stevens County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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