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When to Plant Feverfew in Marion County, OR

Feverfew is a bushy perennial herb with small daisy-like flowers and aromatic leaves. It has been used traditionally for headache relief and is a cheerful garden plant.

Marion County, Oregon is in USDA Zone 8a. The average last spring frost is April 20 and the first fall frost is October 30, giving you a growing season of approximately 193 days.

At an elevation of 422 feet, Marion County receives approximately 50.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Feverfew during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Feverfew root diseases.

Marion County, OR (Zone 8a) Moderate season
193 days
Last Spring Frost April 20
193 growing days
First Fall Frost October 30

Marion County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (20 days to spare)
Transplant: Apr 20 🍅 Harvest: Jul 20 – Oct 5
Recommended (50%) ✓ Fits season (18 days to spare)
Transplant: Apr 27 🍅 Harvest: Jul 27 – Oct 12
Safe Start (90%) ✓ Fits season (24 days to spare)
Transplant: May 16 🍅 Harvest: Aug 15 – Oct 31

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 Marion County

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

Soil pH

Your soil pH (5.4โ€“6.8) overlaps with Feverfew's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.5%) โ€” Feverfew will thrive.

How to Plant Feverfew

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

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 Feverfew

Feverfew 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 Feverfew Needs Rainfall You Supplement Action
Jan โ€” 6.9" 0" โ„๏ธ Dormant
Feb โ€” 5.1" 0" โ„๏ธ Dormant
Mar โ€” 4.9" 0" โ„๏ธ Dormant
Apr 2.2" 3.8" 0" โœ… Rainfall sufficient
May 2.2" 2.8" 0" โœ… Rainfall sufficient
Jun 2.2" 2" 0.2" 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" 1.9" 0.3" ๐Ÿ’ง Light watering
Oct 2.2" 4.2" 0" โœ… Rainfall sufficient
Nov โ€” 8.2" 0" โ„๏ธ Dormant
Dec โ€” 9" 0" โ„๏ธ Dormant

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

Feverfew 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.

Feverfew needs ~1,680 GDD — county provides 3,088 GDD Excellent fit

Feverfew Planting Timeline โ€” Marion County, OR

Feverfew Planting Calendar

Activity When Date Range
Transplant Outdoors April 27 Apr 27 โ€“ May 11
Harvest July 27 Jul 27 โ€“ Oct 12

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 โ€”
July Harvest
August Harvest
September Harvest
October Harvest
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

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

193 days in Marion County

Growing Tips for Feverfew in Marion County

Direct sow Feverfew outdoors after April 20 in Marion County when soil has warmed and frost danger has passed.

Common pests for Feverfew in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors or direct sow on the soil surface. Deadhead regularly to prevent aggressive self-seeding. Divide clumps every 2-3 years to maintain vigor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Feverfew in Marion County, OR?

Marion County is in Zone 8a with an average last frost of April 20. Plan your Feverfew planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Marion County, OR?

Marion County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 20 and first fall frost is October 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Marion 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 Marion County, OR. Local conditions may vary. Last updated: April 2026.