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When to Plant Sunflower in Orting, WA

Pierce County, Washington Zone 8b July

Your July planting checklist for Pierce County, Washington

Your garden in Pierce County, Washington is working on a schedule, even when you're not. Here's where you should be this July.

Avg. last frost April 13
Avg. first frost October 30
Soil temp (4") 90°F
Watering Critical
Pest pressure High
Daylight 15.3 hrs
  1. Pick sunflower

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

August will be here before you know it — start on
  • First harvests: sunflower

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Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Orting, Washington is in USDA Zone 8b. The average last spring frost is April 13 and the first fall frost is October 30, giving you a growing season of approximately 200 days.

At an elevation of 168 feet, Pierce County receives approximately 48.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Sunflower to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Orting, WA (Zone 8b) Long season
200 days
Last Spring Frost April 13
200 growing days
First Fall Frost October 30

Orting Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 14 Transplant: Mar 21 🌸 Bloom: Jun 13 – Oct 31
Recommended (50%) ✗ May not fit
Start indoors: Mar 23 Transplant: Mar 30 🌸 Bloom: Jun 22 – Nov 9
Safe Start (90%) ✗ May not fit
Start indoors: Apr 25 Transplant: May 2 🌸 Bloom: Jul 25 – Dec 12

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 Orting

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

Soil pH

Your soil pH (5.4–6.2) is more acidic than Sunflower prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.4%) — Sunflower will thrive.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

3
successive plantings in your 200-day season

Sow every 8 weeks. Last sowing by Jul 22 to harvest before frost.

Sunflower 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 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 6.8" 0" ❄️ Dormant
Feb 5.7" 0" ❄️ Dormant
Mar 4.4" 0" ❄️ Dormant
Apr 2.2" 4.1" 0" ✅ Rainfall sufficient
May 2.2" 2.8" 0" ✅ Rainfall sufficient
Jun 2.2" 2" 0.2" 💧 Light watering
Jul 2.2" 0.9" 1.3" 🚿 Regular watering
Aug 2.2" 0.9" 1.3" 🚿 Regular watering
Sep 2.2" 2" 0.2" 💧 Light watering
Oct 2.2" 4.7" 0" ✅ Rainfall sufficient
Nov 7.8" 0" ❄️ Dormant
Dec 6.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Pierce County). 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 ~1,041 GDD — county provides 2,450 GDD Excellent fit

Sunflower Planting Timeline — Orting, WA

Sunflower Planting Calendar

Activity When Date Range
Start Indoors March 23 Mar 23 – Apr 6
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 30 Mar 30 – Apr 20
Bloom June 22 Jun 22 – Nov 9

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8b

📆 Growing Season

200 days in Pierce County

Growing Tips for Sunflower in Orting

Direct sow Sunflower outdoors after April 13 in Pierce County 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.

General growing tips

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

🌱

Your Pierce County Garden Planner — Free

A 22-page printable planner built for Pierce County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Pierce County, WA. Local conditions may vary. Last updated: July 2026.