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When to Plant Yarrow in Colfax County, NM

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.

Colfax County, New Mexico is in USDA Zone 5a. The average last spring frost is May 15 and the first fall frost is September 26, giving you a growing season of approximately 134 days.

At an elevation of 5,131 feet, Colfax County receives approximately 15.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Yarrow to ensure they mature before fall. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Yarrow will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Yarrow successfully. Mulch heavily to conserve soil moisture.

Colfax County, NM (Zone 5a) Short season
134 days
Last Spring Frost May 15
134 growing days
First Fall Frost September 26

Colfax County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.1-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 13 🍅 Harvest: Aug 12 – Oct 28
Recommended (50%) ✗ May not fit
Transplant: May 22 🍅 Harvest: Aug 21 – Nov 6
Safe Start (90%) ✗ May not fit
Transplant: Jun 23 🍅 Harvest: Sep 22 – Dec 8

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 Colfax County

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

Soil pH

Your soil pH (7.1โ€“8.1) is more alkaline than Yarrow prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Colfax County warms quickly in spring but drains fast. Yarrow will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Yarrow.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Yarrow.

How to Plant Yarrow

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

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 235 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

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€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 0.9" 0" โ„๏ธ Dormant
Apr โ€” 0.5" 0" โ„๏ธ Dormant
May 2.2" 0.4" 1.8" ๐Ÿšฟ Regular watering
Jun 2.2" 0.5" 1.7" ๐Ÿšฟ Regular watering
Jul 2.2" 3" 0" โœ… Rainfall sufficient
Aug 2.2" 2.9" 0" โœ… Rainfall sufficient
Sep 2.2" 2" 0.2" ๐Ÿ’ง Light watering
Oct โ€” 1.3" 0" โ„๏ธ Dormant
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Colfax 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 ~1,365 GDD — county provides 1,742 GDD Good fit

Yarrow Planting Timeline โ€” Colfax County, NM

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors May 22 May 22 โ€“ Jun 5
Harvest August 21 Aug 21 โ€“ Nov 6

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 Only during dry spells

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

134 days in Colfax County

Growing Tips for Yarrow in Colfax County

Direct sow Yarrow outdoors after May 15 in Colfax County when soil has warmed and frost danger has passed.

Sandy soil in Colfax County dries quickly โ€” mulch Yarrow with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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

Colfax County receives only 16" 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 Colfax County, NM?

Colfax County is in Zone 5a with an average last frost of May 15. Plan your Yarrow planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Colfax County, NM?

Colfax County, New Mexico is in USDA Hardiness Zone 5a. The average last spring frost is May 15 and first fall frost is September 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Colfax County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

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