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When to Plant Daffodils in Asotin County, WA

Asotin County, Washington Zone 7a June

June in the garden — Asotin County, Washington

Here's what deserves your attention in Asotin County, Washington this month. Everything below is tailored to Zone 7a and timed around your local frost dates.

Avg. last frost May 9
Avg. first frost September 30
Soil temp (4") 70°F
Watering Critical
Pest pressure High
Daylight 15.6 hrs

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Daffodils (Narcissus spp.) are among the most dependable and longest-lived of all spring bulbs. Their cheerful yellow and white blooms emerge in early spring, often while frost is still possible, bringing color weeks before most other flowers. Unlike tulips, established clumps naturalize readily — spreading and returning reliably year after year without replanting. Deer and rodents avoid them due to toxic alkaloids in the bulb and sap, making them a low-maintenance choice for naturalized areas, woodland edges, and mixed borders.

Asotin County, Washington is in USDA Zone 7a. The average last spring frost is May 9 and the first fall frost is September 30, giving you a growing season of approximately 144 days.

At an elevation of 2,029 feet, Asotin County receives approximately 14 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Daffodils during the growing season. With low rainfall, drip irrigation is essential for growing Daffodils successfully. Mulch heavily to conserve soil moisture.

Bulb Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting Fragrant
Asotin County, WA (Zone 7a) Short season
144 days
Last Spring Frost May 9
144 growing days
First Fall Frost September 30
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Asotin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Daffodils Planting Risk Windows

Early Start (70% safe) ✓ Fits season (153 days to spare)
Transplant: Apr 28 🌸 Bloom: Mar 31 – Apr 21
Recommended (50%) ✓ Fits season (151 days to spare)
Transplant: May 9 🌸 Bloom: Apr 11 – May 2
Safe Start (90%) ✓ Fits season (144 days to spare)
Transplant: Jun 6 🌸 Bloom: May 9 – May 30

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 Asotin County

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

Soil pH

Your soil pH (5.5–6.5) overlaps with Daffodils's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Daffodils

7"
Planting Depth
7"
Between Plants
8"
Between Rows

Fall planting: Sow 5 weeks before your first frost date for a fall harvest.

Succession Planting Daffodils

8
successive plantings in your 144-day season

Sow every 2.3 weeks. Last sowing by Aug 21 to harvest before frost.

For a dedicated fall crop, sow by Aug 26.

Daffodils Water Budget

Plant needs
0.5″/week
Rainfall provides
0.4″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 117 gal / 100 sq ft

Monthly Watering Guide for Daffodils

Daffodils 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 Daffodils Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 0.9" 0" ❄️ Dormant
May 2.2" 0.8" 1.4" 🚿 Regular watering
Jun 2.2" 0.6" 1.6" 🚿 Regular watering
Jul 2.2" 0.2" 2" 🚿 Regular watering
Aug 2.2" 0.3" 1.9" 🚿 Regular watering
Sep 2.2" 0.5" 1.7" 🚿 Regular watering
Oct 1.2" 0" ❄️ Dormant
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Daffodils 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.

Daffodils needs ~412 GDD — county provides 1,980 GDD Excellent fit

Daffodils Planting Timeline — Asotin County, WA

Daffodils Planting Calendar

Activity When Date Range
Bloom July 29 Jul 29 – Aug 19
Fall Sowing August 26 Aug 26 – Sep 9

Plant 7" deep · 7" apart · Rows 8" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

20–40 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

144 days in Asotin County

Growing Tips for Daffodils in Asotin County

Direct sow Daffodils outdoors after May 09 in Asotin County when soil has warmed and frost danger has passed.

Your generous 144.0-day season in Asotin County allows multiple plantings of Daffodils. Sow every 10.0 days for continuous harvest.

Common pests for Daffodils in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

Asotin County receives only 14" of rain annually. Daffodils needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant bulbs pointed-end up in fall, 6–8 inches deep and 6–8 inches apart in well-drained soil. Allow 12–16 weeks of cold dormancy for proper vernalization. Do not cut back foliage until it turns yellow (6–8 weeks after bloom) — the dying leaves photosynthesize energy into the bulb for next year. Lift and divide overcrowded clumps every 4–5 years in summer after foliage dies back. In zones 7b–9b, select heat-tolerant cultivars (Jonquilla, Tazetta, and Cyclamineus divisions) that perform better with less chill than large-cupped types. Zones 10+: insufficient winter cold; pre-chilling is required but results inconsistent — not recommended for outdoor culture.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Daffodils in Asotin County, WA?

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

What planting zone is Asotin County, WA?

Asotin County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is May 9 and first fall frost is September 30.

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Your Asotin County Garden Planner — Free

A 22-page printable planner built for Asotin County (Zone 7a). 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 Asotin 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.