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When to Plant Leeks in Cusick, WA

Leeks
Pend Oreille County, Washington Zone 6a June

Top priorities for Pend Oreille County, Washington gardeners in June

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Pend Oreille County, Washington.

Avg. last frost May 10
Avg. first frost September 23
Soil temp (4") 57°F
Watering Critical
Pest pressure High
Daylight 15.9 hrs
  1. Start leeks under lights

    You're about 13 weeks out from your last frost — the perfect window to get these germinating indoors.

July prep starts now
  • Fall sowing: leeks

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Leeks are a mild, sweet allium that produces long white shanks. They are more refined than onions and are a key ingredient in soups, stews, and gratins.

Cusick, Washington is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is September 23, giving you a growing season of approximately 136 days.

At an elevation of 3,807 feet, Pend Oreille County receives approximately 13.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Leeks during the growing season. With low rainfall, drip irrigation is essential for growing Leeks successfully. Mulch heavily to conserve soil moisture.

Cusick, WA (Zone 6a) Short season
136 days
Last Spring Frost May 10
136 growing days
First Fall Frost September 23

Cusick Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.6

Drainage

Well Drained

Leeks Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 27 Transplant: May 1 🍅 Harvest: Jul 31 – Oct 16
Recommended (50%) ✗ May not fit
Start indoors: Apr 5 Transplant: May 10 🍅 Harvest: Aug 9 – Oct 25
Safe Start (90%) ✗ May not fit
Start indoors: Apr 26 Transplant: May 31 🍅 Harvest: Aug 30 – Nov 15

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 Cusick

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

Soil pH

Your soil pH (5.3–6.6) is more acidic than Leeks prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Leeks.

Organic Matter

Organic matter is excellent (5.0%) — Leeks will thrive.

How to Plant Leeks

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Leeks Water Budget

Plant needs
0.8″/week
Rainfall provides
0.4″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 765 gal / 100 sq ft

Monthly Watering Guide for Leeks

Leeks needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Leeks Needs Rainfall You Supplement Action
Jan 1.8" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 0.9" 0" ❄️ Dormant
May 3.5" 0.8" 2.7" 🚿 Regular watering
Jun 3.5" 0.5" 3" 🚿 Regular watering
Jul 3.5" 0.2" 3.3" 🚿 Regular watering
Aug 3.5" 0.2" 3.3" 🚿 Regular watering
Sep 3.5" 0.6" 2.9" 🚿 Regular watering
Oct 1.3" 0" ❄️ Dormant
Nov 2.1" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Leeks 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.

Leeks needs ~1,740 GDD — county provides 1,972 GDD Good fit

Leeks Planting Timeline — Cusick, WA

Leeks Planting Calendar

Activity When Date Range
Start Indoors April 5 Apr 5 – Apr 19
Transplant Outdoors May 10 May 10 – May 24
Direct Sow April 26 Apr 26 – May 17
Harvest August 9 Aug 9 – Oct 25
Fall Sowing July 15 Jul 15 – Jul 29

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · 1-2 times/week

📅 Days to Maturity

90–150 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6a

📆 Growing Season

136 days in Pend Oreille County

Growing Tips for Leeks in Cusick

Direct sow Leeks outdoors after May 10 in Pend Oreille County when soil has warmed and frost danger has passed.

Your 136.0-day growing season in Pend Oreille County is tight for Leeks (90.0-150.0 days to maturity). Start indoors and choose early-maturing varieties.

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

General growing tips

Start seeds indoors 10-12 weeks before last frost. Transplant into trenches and hill soil around stems as they grow to increase the white portion. Harvest as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

🌱

Your Pend Oreille County Garden Planner — Free

A 22-page printable planner built for Pend Oreille County (Zone 6a). 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 Pend Oreille County, WA. Local conditions may vary. Last updated: June 2026.