Blog

When to Plant Yarrow in Posey County, IN

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.

Posey County, Indiana is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 28, giving you a growing season of approximately 203 days.

At an elevation of 596 feet, Posey County receives approximately 40.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Yarrow during the growing season.

Posey County, IN (Zone 6b) Long season
203 days
Last Spring Frost April 8
203 growing days
First Fall Frost October 28

Posey County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (28 days to spare)
Transplant: Apr 9 🍅 Harvest: Jul 9 – Sep 24
Recommended (50%) ✓ Fits season (28 days to spare)
Transplant: Apr 15 🍅 Harvest: Jul 15 – Sep 30
Safe Start (90%) ✓ Fits season (36 days to spare)
Transplant: Apr 27 🍅 Harvest: Jul 27 – Oct 12

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 Posey County

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

Soil pH

Your soil pH (6.2โ€“7.0) is within Yarrow's preferred range (5.5โ€“7.0).

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help 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
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 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€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar โ€” 2.7" 0" โ„๏ธ Dormant
Apr 2.2" 3.7" 0" โœ… Rainfall sufficient
May 2.2" 5.2" 0" โœ… Rainfall sufficient
Jun 2.2" 4.7" 0" โœ… Rainfall sufficient
Jul 2.2" 4.4" 0" โœ… Rainfall sufficient
Aug 2.2" 4.4" 0" โœ… Rainfall sufficient
Sep 2.2" 3" 0" โœ… Rainfall sufficient
Oct 2.2" 3.5" 0" โœ… Rainfall sufficient
Nov โ€” 2.7" 0" โ„๏ธ Dormant
Dec โ€” 2.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Posey 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 ~1,522 GDD — county provides 2,943 GDD Excellent fit

Yarrow Planting Timeline โ€” Posey County, IN

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors April 15 Apr 15 โ€“ Apr 29
Harvest July 15 Jul 15 โ€“ Sep 30

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 โ€”
June โ€”
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

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

203 days in Posey County

Growing Tips for Yarrow in Posey County

Direct sow Yarrow outdoors after April 08 in Posey County when soil has warmed and frost danger has passed.

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

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 Posey County, IN?

Posey County is in Zone 6b with an average last frost of April 8. Plan your Yarrow planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Posey County, IN?

Posey County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 28.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Posey County gardeners in Zone 6b 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 Posey County, IN. Local conditions may vary. Last updated: April 2026.