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When to Plant Bleeding Hearts in Whatcom County, WA

Whatcom County, Washington Zone 8a June

Top priorities for Whatcom County, Washington gardeners in June

Your Whatcom County, Washington garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 6
Avg. first frost October 29
Soil temp (4") 77°F
Watering High
Pest pressure High
Daylight 15.9 hrs
  1. Indoor seed-starting week for bleeding hearts

    You're about 19 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. It's harvest week for bleeding hearts

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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Bleeding Hearts (Lamprocapnos spectabilis) are elegant woodland perennials producing arching stems hung with distinctive heart-shaped pink or white flowers with protruding inner petals — the "drops" beneath each heart. A beloved heirloom perennial from Asia, bleeding hearts emerge vigorously in spring, bloom prolifically for 4–6 weeks, and then go dormant in summer heat — a natural die-back that is entirely normal. The dormancy gap should be planned for by interplanting with summer-emerging hostas, ferns, or impatiens. Fringed bleeding heart (Dicentra eximia), a US native, has a longer bloom season and does not go fully dormant. All parts are toxic if ingested.

Whatcom County, Washington is in USDA Zone 8a. The average last spring frost is April 6 and the first fall frost is October 29, giving you a growing season of approximately 206 days.

At an elevation of 386 feet, Whatcom County receives approximately 49 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Bleeding Hearts during the growing season.

Perennial Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Whatcom County, WA (Zone 8a) Long season
206 days
Last Spring Frost April 6
206 growing days
First Fall Frost October 29

Whatcom County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.4

Drainage

Well Drained

Bleeding Hearts Planting Risk Windows

Early Start (70% safe) ✓ Fits season (132 days to spare)
Start indoors: Jan 28 Transplant: Mar 25 🌸 Bloom: May 13 – Jun 10
Recommended (50%) ✓ Fits season (129 days to spare)
Start indoors: Feb 9 Transplant: Apr 6 🌸 Bloom: May 25 – Jun 22
Safe Start (90%) ✓ Fits season (122 days to spare)
Start indoors: Mar 11 Transplant: May 6 🌸 Bloom: Jun 24 – Jul 22

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 Whatcom County

How your county's soil matches Bleeding Hearts's growing requirements.

Soil pH

Your soil pH (5.2–6.4) is more acidic than Bleeding Hearts prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Bleeding Hearts will thrive.

How to Plant Bleeding Hearts

1.5"
Planting Depth
24"
Between Plants
30"
Between Rows

Succession Planting Bleeding Hearts

4
successive plantings in your 206-day season

Sow every 6.9 weeks. Last sowing by Jul 31 to harvest before frost.

Bleeding Hearts Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Only during dry spells
Season total 2 gal / 100 sq ft

Monthly Watering Guide for Bleeding Hearts

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

Month Bleeding Hearts Needs Rainfall You Supplement Action
Jan 6.1" 0" ❄️ Dormant
Feb 6.2" 0" ❄️ Dormant
Mar 4.3" 0" ❄️ Dormant
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 3.1" 1.2" 💧 Light watering
Jun 4.3" 2.1" 2.2" 🚿 Regular watering
Jul 4.3" 0.7" 3.6" 🚿 Regular watering
Aug 4.3" 0.9" 3.4" 🚿 Regular watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 4.5" 0" ✅ Rainfall sufficient
Nov 7.1" 0" ❄️ Dormant
Dec 8.2" 0" ❄️ Dormant

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

Bleeding Hearts 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.

Bleeding Hearts needs ~1,031 GDD — county provides 2,832 GDD Excellent fit

Bleeding Hearts Planting Timeline — Whatcom County, WA

Bleeding Hearts Planting Calendar

Activity When Date Range
Start Indoors February 9 Feb 9 – Feb 23
Transplant Outdoors April 6 Apr 6 – Apr 20
Bloom May 25 May 25 – Jun 22

Plant 1.5" deep · 24" apart · Rows 30" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8a

📆 Growing Season

206 days in Whatcom County

Growing Tips for Bleeding Hearts in Whatcom County

Direct sow Bleeding Hearts outdoors after April 06 in Whatcom County when soil has warmed and frost danger has passed.

General growing tips

Plant bare-root crowns in early spring as soon as soil is workable, or in fall at least 6 weeks before hard freeze. Set eyes 1–2 inches below soil level. Morning sun with afternoon shade is ideal; deep shade is tolerated but reduces bloom. Keep moist but well-drained — will not tolerate waterlogged soil. After flowering, the foliage will yellow and die back in summer heat — this is normal. Do not cut back until foliage turns fully yellow; the plant is storing energy. Mark the location to avoid disturbing crowns during summer dormancy. Divide every 4–5 years in early spring. Year 2+ plants produce the fullest flowering display.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Bleeding Hearts in Whatcom County, WA?

Whatcom County is in Zone 8a with an average last frost of April 6. Plan your Bleeding Hearts planting based on this frost date — see the calendar above for exact timing.

What planting zone is Whatcom County, WA?

Whatcom County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 6 and first fall frost is October 29.

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Your Whatcom County Garden Planner — Free

A 22-page printable planner built for Whatcom County (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 Whatcom 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.