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When to Plant Dill in Clackamas County, OR

Dill is a feathery annual herb with aromatic leaves and seeds. Its fine foliage and umbrella-shaped flower heads attract beneficial insects to the garden.

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 Dill during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Dill 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 (99 days to spare)
Start indoors: Feb 28 Transplant: Mar 28 🍅 Harvest: May 9 – Jul 11
Recommended (50%) ✓ Fits season (99 days to spare)
Start indoors: Mar 10 Transplant: Apr 7 🍅 Harvest: May 19 – Jul 21
Safe Start (90%) ✓ Fits season (103 days to spare)
Start indoors: Apr 2 Transplant: Apr 30 🍅 Harvest: Jun 11 – Aug 13

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 Dill's growing requirements.

Soil pH

Your soil pH (5.7โ€“6.3) is within Dill's preferred range (5.5โ€“7.0).

Soil Texture

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

Organic Matter

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

How to Plant Dill

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

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

Succession Planting Dill

5
successive plantings in your 197-day season

Sow every 4.6 weeks. Last sowing by Aug 29 to harvest before frost.

For a dedicated fall crop, sow by Aug 19.

Plant Water Budget

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

Monthly Watering Guide for Dill

Dill needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Dill 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 2.2" 4" 0" โœ… Rainfall sufficient
May 2.2" 3.3" 0" โœ… Rainfall sufficient
Jun 2.2" 2.1" 0.1" ๐Ÿ’ง Light watering
Jul 2.2" 0.8" 1.4" ๐Ÿšฟ Regular watering
Aug 2.2" 1" 1.2" ๐Ÿšฟ Regular watering
Sep 2.2" 2.2" 0" โœ… Rainfall sufficient
Oct 2.2" 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.

Dill 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.

Dill needs ~688 GDD — county provides 2,708 GDD Excellent fit

Dill Planting Timeline โ€” Clackamas County, OR

Dill Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 โ€“ Mar 24
Transplant Outdoors April 7 Apr 7 โ€“ Apr 21
Direct Sow March 31 Mar 31 โ€“ Apr 21
Harvest May 19 May 19 โ€“ Jul 21
Fall Sowing August 19 Aug 19 โ€“ Sep 2

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July Harvest
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

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

197 days in Clackamas County

Growing Tips for Dill in Clackamas County

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

Your generous 197.0-day season in Clackamas County allows multiple plantings of Dill. Sow every 20.0 days for continuous harvest.

Common pests for Dill 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 as dill has a taproot and dislikes transplanting. Succession sow for continuous leaf harvest. Allow some plants to flower for seeds and to attract beneficial insects.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Dill in Clackamas County, OR?

Clackamas County is in Zone 8a with an average last frost of April 14. Plan your Dill 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.