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When to Plant Sunflower in Prince of Wales-Hyder, AK

Prince of Wales-Hyder, Alaska Zone 8a May

What to do in May

A quick May briefing for Prince of Wales-Hyder, Alaska gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 13
Avg. first frost November 1
Soil temp (4") 66°F
Watering Critical
Pest pressure Moderate
Daylight 16 hrs
June will be here before you know it — start on
  • Starting indoors: sunflower

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Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.

Prince of Wales-Hyder, Alaska is in USDA Zone 8a. The average last spring frost is April 13 and the first fall frost is November 1, giving you a growing season of approximately 202 days.

At an elevation of 257 feet, Prince of Wales-Hyder receives approximately 14.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 70°F, so choose short-season varieties of Sunflower to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Sunflower successfully. Mulch heavily to conserve soil moisture.

Prince of Wales-Hyder, AK (Zone 8a) Long season
202 days
Last Spring Frost April 13
202 growing days
First Fall Frost November 1

Prince of Wales-Hyder Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (67 days to spare)
Start indoors: Feb 20 Transplant: Apr 24 🍅 Harvest: Jul 3 – Aug 21
Recommended (50%) ✓ Fits season (69 days to spare)
Start indoors: Feb 23 Transplant: Apr 27 🍅 Harvest: Jul 6 – Aug 24
Safe Start (90%) ✓ Fits season (79 days to spare)
Start indoors: Mar 13 Transplant: May 15 🍅 Harvest: Jul 24 – Sep 11

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 Prince of Wales-Hyder

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

Soil pH

Your soil pH (5.2–6.8) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Prince of Wales-Hyder is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Sunflower prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is excellent (6.0%) — Sunflower will thrive.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
30"
Between Rows

Succession Planting Sunflower

3
successive plantings in your 202-day season

Sow every 8 weeks. Last sowing by Jul 24 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.3″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 91 gal / 100 sq ft

Monthly Watering Guide for Sunflower

Sunflower 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 Sunflower Needs Rainfall You Supplement Action
Jan 0.8" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 0.6" 0" ❄️ Dormant
Apr 2.2" 0.4" 1.8" 🚿 Regular watering
May 2.2" 0.7" 1.5" 🚿 Regular watering
Jun 2.2" 1" 1.2" 🚿 Regular watering
Jul 2.2" 1.6" 0.6" 💧 Light watering
Aug 2.2" 1.9" 0.3" 💧 Light watering
Sep 2.2" 2.8" 0" ✅ Rainfall sufficient
Oct 2.2" 1.7" 0.5" 💧 Light watering
Nov 2.2" 1.1" 1.1" 🚿 Regular watering
Dec 0.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Prince of Wales-Hyder). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sunflower 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.

Sunflower needs ~212 GDD — county provides 505 GDD Excellent fit

Sunflower Planting Timeline — Prince of Wales-Hyder, AK

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors April 27 Apr 27 – May 11
Direct Sow April 20 Apr 20 – May 11
Harvest July 6 Jul 6 – Aug 24

Plant 1" deep · 18" apart · Rows 30" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

202 days in Prince of Wales-Hyder

Growing Tips for Sunflower in Prince of Wales-Hyder

Direct sow Sunflower outdoors after April 13 in Prince of Wales-Hyder when soil has warmed and frost danger has passed.

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Prince of Wales-Hyder receives only 14" of rain annually. Sunflower needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Prince of Wales-Hyder, AK?

Prince of Wales-Hyder is in Zone 8a with an average last frost of April 13. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Prince of Wales-Hyder, AK?

Prince of Wales-Hyder, Alaska is in USDA Hardiness Zone 8a. The average last spring frost is April 13 and first fall frost is November 1.

🌱

Your Prince of Wales-Hyder Garden Planner — Free

A 24-page printable planner built for Prince of Wales-Hyder (Zone 8a). 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 Prince of Wales-Hyder, AK. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.