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When to Plant Caraway in Washington County, OR

Caraway is a biennial herb grown for its distinctive crescent-shaped seeds used in rye bread, sauerkraut, and European cuisine. The leaves and roots are also edible.

Washington County, Oregon is in USDA Zone 8b. The average last spring frost is April 15 and the first fall frost is October 27, giving you a growing season of approximately 195 days.

At an elevation of 352 feet, Washington County receives approximately 47.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Caraway during the growing season.

Washington County, OR (Zone 8b) Moderate season
195 days
Last Spring Frost April 15
195 growing days
First Fall Frost October 27

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Start indoors: Mar 4 Transplant: Apr 1
Recommended (50%) ✓ Fits season
Start indoors: Mar 11 Transplant: Apr 8
Safe Start (90%) ✓ Fits season
Start indoors: Apr 3 Transplant: May 1

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 Washington County

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

Soil pH

Your soil pH (5.8โ€“6.4) overlaps with Caraway's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Washington County is excellent for Caraway โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.7%) โ€” Caraway will thrive.

How to Plant Caraway

0.5"
Planting Depth
8"
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
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Caraway

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

Month Caraway Needs Rainfall You Supplement Action
Jan โ€” 7.4" 0" โ„๏ธ Dormant
Feb โ€” 5.7" 0" โ„๏ธ Dormant
Mar โ€” 4.2" 0" โ„๏ธ Dormant
Apr 4.3" 3" 1.3" ๐Ÿ’ง Light watering
May 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Jun 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Jul 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
Aug 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Sep 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Oct 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Nov โ€” 7.3" 0" โ„๏ธ Dormant
Dec โ€” 8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Washington County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Caraway 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" โ€” every day above 50ยฐF 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.

Caraway needs ~5,603 GDD — county provides 2,681 GDD May not mature

Caraway Planting Timeline โ€” Washington County, OR

Caraway Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 โ€“ Mar 25
Transplant Outdoors April 8 Apr 8 โ€“ Apr 22
Direct Sow April 1 Apr 1 โ€“ Apr 22
Fall Sowing August 18 Aug 18 โ€“ Sep 1

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

365โ€“450 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

195 days in Washington County

Growing Tips for Caraway in Washington County

Direct sow Caraway outdoors after April 15 in Washington County when soil has warmed and frost danger has passed.

Your 195.0-day growing season in Washington County is tight for Caraway (365.0-450.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Caraway in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Caraway produces seeds in its second year. Harvest seed heads when they turn brown. The young leaves can be used like parsley.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Caraway in Washington County, OR?

Washington County is in Zone 8b with an average last frost of April 15. Plan your Caraway planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, OR?

Washington County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 15 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washington County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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