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When to Plant Chives in Clackamas County, OR

Chives are a hardy perennial herb with a mild onion flavor and attractive purple pom-pom flowers. They are one of the easiest herbs to grow and maintain.

Clackamas County, Oregon is in USDA Zone 8a. The average last spring frost is April 14 and the first fall frost is October 28, giving you a growing season of approximately 197 days.

At an elevation of 199 feet, Clackamas County receives approximately 53.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Chives during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Chives root diseases.

Clackamas County, OR (Zone 8a) Moderate season
197 days
Last Spring Frost April 14
197 growing days
First Fall Frost October 28

Clackamas County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (57 days to spare)
Transplant: Apr 11 🍅 Harvest: Jun 13 – Aug 22
Recommended (50%) ✓ Fits season (57 days to spare)
Transplant: Apr 21 🍅 Harvest: Jun 23 – Sep 1
Safe Start (90%) ✓ Fits season (61 days to spare)
Transplant: May 14 🍅 Harvest: Jul 16 – Sep 24

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 Clackamas County

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

Soil pH

Your soil pH (5.7โ€“6.3) overlaps with Chives's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Chives

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Chives

3
successive plantings in your 197-day season

Sow every 6.9 weeks. Last sowing by Jul 30 to harvest before frost.

Plant Water Budget

Plant needs
0.4″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Chives

Chives needs approximately 0.4 inches of water per week (1.7" per month). Here's how your county's rainfall compares month by month.

Month Chives Needs Rainfall You Supplement Action
Jan โ€” 8.3" 0" โ„๏ธ Dormant
Feb โ€” 5.3" 0" โ„๏ธ Dormant
Mar โ€” 4.8" 0" โ„๏ธ Dormant
Apr 1.7" 4" 0" โœ… Rainfall sufficient
May 1.7" 3.3" 0" โœ… Rainfall sufficient
Jun 1.7" 2.1" 0" โœ… Rainfall sufficient
Jul 1.7" 0.8" 0.9" ๐Ÿšฟ Regular watering
Aug 1.7" 1" 0.7" ๐Ÿ’ง Light watering
Sep 1.7" 2.2" 0" โœ… Rainfall sufficient
Oct 1.7" 4.7" 0" โœ… Rainfall sufficient
Nov โ€” 8.2" 0" โ„๏ธ Dormant
Dec โ€” 8.5" 0" โ„๏ธ Dormant

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

Chives 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.

Chives needs ~1,031 GDD — county provides 2,708 GDD Excellent fit

Chives Planting Timeline โ€” Clackamas County, OR

Chives Planting Calendar

Activity When Date Range
Transplant Outdoors April 21 Apr 21 โ€“ May 5
Harvest June 23 Jun 23 โ€“ Sep 1

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.4"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

197 days in Clackamas County

Growing Tips for Chives in Clackamas County

Direct sow Chives outdoors after April 14 in Clackamas County when soil has warmed and frost danger has passed.

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

General growing tips

Start from seed or divisions in spring. Cut back to 2 inches after flowering to encourage fresh growth. Both the leaves and flowers are edible and delicious.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chives in Clackamas County, OR?

Clackamas County is in Zone 8a with an average last frost of April 14. Plan your Chives planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clackamas County, OR?

Clackamas County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 14 and first fall frost is October 28.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clackamas County gardeners in Zone 8a 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 Clackamas County, OR. Local conditions may vary. Last updated: April 2026.