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When to Plant Crosne in Asotin County, WA

Asotin County, Washington Zone 7a May

May in the garden — Asotin County, Washington

May is a pivotal month for Asotin County, Washington gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 9
Avg. first frost September 30
Soil temp (4") 59°F
Watering Critical
Pest pressure Low
Daylight 14.8 hrs

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Crosne (Chinese artichoke) produces small, segmented white tubers with a crunchy texture and mild artichoke-nutty flavor. They are a rare delicacy in French cuisine.

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 Crosne during the growing season. With low rainfall, drip irrigation is essential for growing Crosne successfully. Mulch heavily to conserve soil moisture.

Asotin County, WA (Zone 7a) Short season
144 days
Last Spring Frost May 9
144 growing days
First Fall Frost September 30

Asotin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 28 🍅 Harvest: Sep 29 – Dec 1
Recommended (50%) ✗ May not fit
Transplant: May 9 🍅 Harvest: Oct 10 – Dec 12
Safe Start (90%) ✓ Fits season (285 days to spare)
Transplant: Jun 6 🍅 Harvest: Nov 7 – Jan 9

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 Crosne's growing requirements.

Soil pH

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

Soil Texture

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

Organic Matter

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

How to Plant Crosne

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 758 gal / 100 sq ft

Monthly Watering Guide for Crosne

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

Month Crosne 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 4.3" 0.8" 3.5" 🚿 Regular watering
Jun 4.3" 0.6" 3.7" 🚿 Regular watering
Jul 4.3" 0.2" 4.1" 🚿 Regular watering
Aug 4.3" 0.3" 4" 🚿 Regular watering
Sep 4.3" 0.5" 3.8" 🚿 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.

Crosne 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.

Crosne needs ~2,406 GDD — county provides 1,980 GDD May not mature

Crosne Planting Timeline — Asotin County, WA

Crosne Planting Calendar

Activity When Date Range
Direct Sow April 25 Apr 25 – May 16
Harvest September 26 Sep 26 – Nov 28
Fall Sowing July 22 Jul 22 – Aug 5

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

150–200 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

144 days in Asotin County

Growing Tips for Crosne in Asotin County

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

Your 144.0-day growing season in Asotin County is tight for Crosne (150.0-200.0 days to maturity). Start indoors and choose early-maturing varieties.

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

General growing tips

Plant tubers 3 inches deep in spring. Mark the location well as plants die back. Harvest in late fall after frost. Leave some tubers in ground for next year. Very labor-intensive to harvest.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crosne in Asotin County, WA?

Asotin County is in Zone 7a with an average last frost of May 9. Plan your Crosne 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 24-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: May 2026.

Sources & credits

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