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When to Plant Crosne in Josephine County, OR

Josephine County, Oregon Zone 8b May

Top priorities for Josephine County, Oregon gardeners in May

Each item below is timed to Josephine County, Oregon's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 22
Avg. first frost October 20
Soil temp (4") 69°F
Watering High
Pest pressure High
Daylight 14.4 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.

Josephine County, Oregon is in USDA Zone 8b. The average last spring frost is April 22 and the first fall frost is October 20, giving you a growing season of approximately 181 days.

At an elevation of 340 feet, Josephine County receives approximately 52.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Crosne during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Crosne root diseases.

Josephine County, OR (Zone 8b) Moderate season
181 days
Last Spring Frost April 22
181 growing days
First Fall Frost October 20
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Josephine County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 9 🍅 Harvest: Sep 10 – Nov 12
Recommended (50%) ✗ May not fit
Transplant: Apr 22 🍅 Harvest: Sep 23 – Nov 25
Safe Start (90%) ✗ May not fit
Transplant: May 12 🍅 Harvest: Oct 13 – Dec 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 Josephine County

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

Soil pH

Your soil pH (5.7–6.2) is more acidic than Crosne prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.4%) — 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
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 8.4" 0" ❄️ Dormant
Feb 6.6" 0" ❄️ Dormant
Mar 6.2" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 2.7" 1.6" 💧 Light watering
Jun 4.3" 2" 2.3" 🚿 Regular watering
Jul 4.3" 0.8" 3.5" 🚿 Regular watering
Aug 4.3" 0.9" 3.4" 🚿 Regular watering
Sep 4.3" 1.9" 2.4" 🚿 Regular watering
Oct 4.3" 4.4" 0" ✅ Rainfall sufficient
Nov 7.4" 0" ❄️ Dormant
Dec 8.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Josephine 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 ~3,062 GDD — county provides 3,167 GDD Good fit

Crosne Planting Timeline — Josephine County, OR

Crosne Planting Calendar

Activity When Date Range
Direct Sow April 8 Apr 8 – Apr 29
Harvest September 9 Sep 9 – Nov 11
Fall Sowing August 11 Aug 11 – Aug 25

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

150–200 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8b

📆 Growing Season

181 days in Josephine County

Growing Tips for Crosne in Josephine County

Direct sow Crosne outdoors after April 22 in Josephine County when soil has warmed and frost danger has passed.

Your 181.0-day growing season in Josephine County is tight for Crosne (150.0-200.0 days to maturity). Start indoors and choose early-maturing varieties.

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 Josephine County, OR?

Josephine County is in Zone 8b with an average last frost of April 22. Plan your Crosne planting based on this frost date — see the calendar above for exact timing.

What planting zone is Josephine County, OR?

Josephine County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 22 and first fall frost is October 20.

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Your Josephine County Garden Planner — Free

A 24-page printable planner built for Josephine County (Zone 8b). 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 Josephine County, OR. 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.