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When to Plant Crosne in Jefferson County, OR

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.

Jefferson County, Oregon is in USDA Zone 7a. The average last spring frost is June 9 and the first fall frost is September 19, giving you a growing season of approximately 102 days.

At an elevation of 21 feet, Jefferson County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79°F, so choose short-season varieties of Crosne to ensure they mature before fall.

Jefferson County, OR (Zone 7a) Short season
102 days
Last Spring Frost June 9
102 growing days
First Fall Frost September 19

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.7

Drainage

Well Drained

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 4.8" 0" ❄️ Dormant
Feb 3.7" 0" ❄️ Dormant
Mar 3.7" 0" ❄️ Dormant
Apr 2.9" 0" ❄️ Dormant
May 1.8" 0" ❄️ Dormant
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 0.5" 3.8" 🚿 Regular watering
Aug 4.3" 0.6" 3.7" 🚿 Regular watering
Sep 4.3" 1.6" 2.7" 🚿 Regular watering
Oct 3.2" 0" ❄️ Dormant
Nov 6.1" 0" ❄️ Dormant
Dec 5.5" 0" ❄️ Dormant

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

Crosne Planting Timeline — Jefferson County, OR

Crosne Planting Calendar

Activity When Date Range
Direct Sow May 26 May 26 – Jun 16
Harvest October 27 Oct 27 – Dec 29
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

150–200 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

102 days in Jefferson County

Growing Tips for Jefferson County

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 Jefferson County, OR?

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

What planting zone is Jefferson County, OR?

Jefferson County, Oregon is in USDA Hardiness Zone 7a. The average last spring frost is June 9 and first fall frost is September 19.

🌱

Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jefferson County, OR. Local conditions may vary. Last updated: July 2026.

Sources & credits

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