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When to Plant Yarrow in Wheeler County, OR

Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.

Wheeler County, Oregon is in USDA Zone 5b. The average last spring frost is May 23 and the first fall frost is September 23, giving you a growing season of approximately 123 days.

At an elevation of 2,175 feet, Wheeler County receives approximately 22.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Yarrow to ensure they mature before fall.

Wheeler County, OR (Zone 5b) Short season
123 days
Last Spring Frost May 23
123 growing days
First Fall Frost September 23

Wheeler County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 23 🍅 Harvest: Aug 22 – Nov 7
Recommended (50%) ✗ May not fit
Transplant: May 30 🍅 Harvest: Aug 29 – Nov 14
Safe Start (90%) ✗ May not fit
Transplant: Jun 26 🍅 Harvest: Sep 25 – Dec 11

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 Wheeler County

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

Soil pH

Your soil pH (5.2โ€“6.3) overlaps with Yarrow's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

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

How to Plant Yarrow

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

Plant Water Budget

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

Monthly Watering Guide for Yarrow

Yarrow 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 Yarrow Needs Rainfall You Supplement Action
Jan โ€” 3" 0" โ„๏ธ Dormant
Feb โ€” 2.3" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr โ€” 1.6" 0" โ„๏ธ Dormant
May 2.2" 1.5" 0.7" ๐Ÿ’ง Light watering
Jun 2.2" 1" 1.2" ๐Ÿšฟ Regular watering
Jul 2.2" 0.4" 1.8" ๐Ÿšฟ Regular watering
Aug 2.2" 0.4" 1.8" ๐Ÿšฟ Regular watering
Sep 2.2" 0.8" 1.4" ๐Ÿšฟ Regular watering
Oct โ€” 2.1" 0" โ„๏ธ Dormant
Nov โ€” 3.3" 0" โ„๏ธ Dormant
Dec โ€” 3.8" 0" โ„๏ธ Dormant

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

Yarrow 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.

Yarrow needs ~1,286 GDD — county provides 1,506 GDD Good fit

Yarrow Planting Timeline โ€” Wheeler County, OR

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors May 30 May 30 โ€“ Jun 13
Harvest August 29 Aug 29 โ€“ Nov 14

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June Transplant Outdoors
July โ€”
August Harvest
September Harvest
October Harvest
November Harvest
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 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

123 days in Wheeler County

Growing Tips for Yarrow in Wheeler County

Direct sow Yarrow outdoors after May 23 in Wheeler County when soil has warmed and frost danger has passed.

Your 123.0-day growing season in Wheeler County is tight for Yarrow (90.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Wheeler County receives only 23" of rain annually. Yarrow needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Yarrow in Wheeler County, OR?

Wheeler County is in Zone 5b with an average last frost of May 23. Plan your Yarrow planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Wheeler County, OR?

Wheeler County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is May 23 and first fall frost is September 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Wheeler County gardeners in Zone 5b 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 Wheeler County, OR. Local conditions may vary. Last updated: April 2026.