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When to plant Petunia in Dillingham Census Area, AK

In Dillingham Census Area, Petunia is a spring-only crop. Plant May 8–May 22 once soil hits 50°F.

When to Plant Petunia in Dillingham Census Area, AK

Dillingham Census Area, Alaska Zone 4b June

What to do in June

Here's what deserves your attention in Dillingham Census Area, Alaska this month. Everything below is tailored to Zone 4b and timed around your local frost dates.

Soil temp (4") 58°F
Watering Moderate
Pest pressure Moderate
Daylight 18.4 hrs

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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.

Dillingham Census Area, Alaska is in USDA Zone 4b. The average last spring frost is May 1 and the first fall frost is September 6, giving you a growing season of approximately 128 days.

At an elevation of 410 feet, Dillingham Census Area receives approximately 54 inches of rainfall annually with predominantly silt loam soil. Summer highs average 60°F, so choose short-season varieties of Petunia to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Petunia root diseases.

Annual Blooms in Summer Pollinator-friendly Fragrant
Dillingham Census Area, AK (Zone 4b) Short season
128 days
Last Spring Frost May 1
128 growing days
First Fall Frost September 6

Dillingham Census Area Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.2

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (29 days to spare)
Start indoors: Feb 11 Transplant: Apr 22 🌸 Bloom: Jul 1 – Sep 16
Recommended (50%) ✓ Fits season (29 days to spare)
Start indoors: Feb 11 Transplant: Apr 22 🌸 Bloom: Jul 1 – Sep 16
Safe Start (90%) ✓ Fits season (29 days to spare)
Start indoors: Feb 11 Transplant: Apr 22 🌸 Bloom: Jul 1 – Sep 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 Dillingham Census Area

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

Soil pH

Your soil pH (5.0–6.2) is more acidic than Petunia prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Petunia.

Organic Matter

Organic matter is excellent (6.6%) — Petunia will thrive.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
1.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 2.6" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 1.8" 0" ❄️ Dormant
May 4.3" 2.3" 2" 💧 Light watering
Jun 4.3" 3.5" 0.8" 💧 Light watering
Jul 4.3" 7.3" 0" ✅ Rainfall sufficient
Aug 4.3" 8.4" 0" ✅ Rainfall sufficient
Sep 4.3" 9.5" 0" ✅ Rainfall sufficient
Oct 6.5" 0" ❄️ Dormant
Nov 4.2" 0" ❄️ Dormant
Dec 3.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Dillingham Census Area). 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 ~0 GDD — county provides 0 GDD May not mature

Petunia Planting Timeline — Dillingham Census Area, AK

Petunia Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors May 8 May 8 – May 22
Bloom July 17 Jul 17 – Oct 2

· 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 · Natural rainfall sufficient

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 4b

📆 Growing Season

128 days in Dillingham Census Area

Growing Tips for Petunia in Dillingham Census Area

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 Dillingham Census Area, AK?

Dillingham Census Area is in Zone 4b with an average last frost of May 1. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dillingham Census Area, AK?

Dillingham Census Area, Alaska is in USDA Hardiness Zone 4b. The average last spring frost is May 1 and first fall frost is September 6.

When should I plant Petunia in Dillingham Census Area, AK?

In Dillingham Census Area, AK, plant Petunia after the last frost (around May 1) and before the first frost (around September 6). Best results when soil holds above 50°F.

What growing zone is Dillingham Census Area, AK for Petunia?

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

Can Petunia grow in Dillingham Census Area's climate?

Yes — Petunia grows well in Dillingham Census Area's temperate climate. Dillingham Census Area averages a 128-day frost-free season, with last frost around May 1 and first frost around September 6.

🌱

Your Dillingham Census Area Garden Planner — Free

A 22-page printable planner built for Dillingham Census Area (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 Dillingham Census Area, AK. Local conditions may vary. Last updated: June 2026.

Sources & credits

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