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When to Plant Anemones in King County, WA

King County, Washington Zone 9a June

King County, Washington gardeners: here's your June plan

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

Avg. last frost April 7
Avg. first frost October 30
Soil temp (4") 79°F
Watering High
Pest pressure High
Daylight 15.7 hrs

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Poppy anemones (Anemone coronaria) produce vivid, poppy-like flowers with striking black centers, in shades of red, blue, purple, white, and bicolor. A cool-season cut flower favorite, they thrive in the mild overlap between winter's end and summer's arrival. In mild-winter zones (7+), fall planting yields a spectacular mid-spring bloom flush that florists prize. In colder zones, spring planting produces summer flowers. The 'Meron' and 'Moissonnier' series dominate commercial cut flower production; 'De Caen' and 'St. Brigid' are standard home garden strains.

King County, Washington is in USDA Zone 9a. The average last spring frost is April 7 and the first fall frost is October 30, giving you a growing season of approximately 206 days.

At an elevation of 258 feet, King County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Anemones during the growing season.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
King County, WA (Zone 9a) Long season
206 days
Last Spring Frost April 7
206 growing days
First Fall Frost October 30

King County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.4

Drainage

Well Drained

Anemones Planting Risk Windows

Early Start (70% safe) ✓ Fits season (169 days to spare)
Transplant: Mar 24 🌸 Bloom: Mar 31 – Apr 28
Recommended (50%) ✓ Fits season (171 days to spare)
Transplant: Apr 7 🌸 Bloom: Apr 14 – May 12
Safe Start (90%) ✓ Fits season (150 days to spare)
Transplant: May 20 🌸 Bloom: May 27 – Jun 24

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 King County

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

Soil pH

Your soil pH (5.7–6.4) is within Anemones's preferred range (5.5–6.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (5.5%) — Anemones will thrive.

How to Plant Anemones

3"
Planting Depth
5"
Between Plants
6"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Anemones Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 428 gal / 100 sq ft

Monthly Watering Guide for Anemones

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

Month Anemones Needs Rainfall You Supplement Action
Jan 5.9" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 4.3" 2.9" 1.4" 💧 Light watering
May 4.3" 2" 2.3" 🚿 Regular watering
Jun 4.3" 1.3" 3" 🚿 Regular watering
Jul 4.3" 0.6" 3.7" 🚿 Regular watering
Aug 4.3" 0.7" 3.6" 🚿 Regular watering
Sep 4.3" 1.6" 2.7" 🚿 Regular watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 5.6" 0" ❄️ Dormant
Dec 5.7" 0" ❄️ Dormant

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

Anemones 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.

Anemones needs ~1,759 GDD — county provides 3,450 GDD Excellent fit

Anemones Planting Timeline — King County, WA

Anemones Planting Calendar

Activity When Date Range
Bloom September 11 Sep 11 – Oct 9
Fall Sowing September 4 Sep 4 – Sep 18

Plant 3" deep · 5" apart · Rows 6" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August
September Fall Sowing Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: ideal

🗺️ USDA Zone

Zone 9a

📆 Growing Season

206 days in King County

Growing Tips for Anemones in King County

Direct sow Anemones outdoors after April 07 in King County when soil has warmed and frost danger has passed.

General growing tips

Soak corms in tepid water for 2–4 hours before planting to rehydrate them. Plant 2–3 inches deep with the flat or rough side down (corms are irregular). Space 4–6 inches apart. Anemones are cool-season plants — they need cool temperatures to set buds; summer heat causes dormancy. In zones 7+, fall planting allows corms to root through winter and bloom in March–April. In zones 5–6, start corms indoors 4 weeks before last frost, then transplant after danger of hard freeze passes. In zones 9–10b, plant from October through January for a succession of blooms. After bloom, allow foliage to die back; corms can be lifted, dried, and stored in a cool, dry place through summer.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Anemones in King County, WA?

King County is in Zone 9a with an average last frost of April 7. Plan your Anemones planting based on this frost date — see the calendar above for exact timing.

What planting zone is King County, WA?

King County, Washington is in USDA Hardiness Zone 9a. The average last spring frost is April 7 and first fall frost is October 30.

🌱

Your King County Garden Planner — Free

A 22-page printable planner built for King County (Zone 9a). 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 King County, WA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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