Blog

When to plant Yarrow in Marshall County County,

For Yarrow in Marshall County County, the safe spring window opens around April 3 and closes around April 24. Last expected frost is April 3, first fall frost November 1, giving a 212-day growing season.

When to Plant Yarrow in Marshall County, KY

Marshall County, Kentucky Zone 7a June

June in Marshall County, Kentucky — your action list

Welcome to June in Zone 7a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 3
Avg. first frost November 1
Soil temp (4") 71°F
Watering Moderate
Pest pressure High
Daylight 14.5 hrs
  1. Begin indoor sowing: yarrow

    Label every cell. You will absolutely forget which is which otherwise.

  2. It's harvest week for yarrow

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Get ahead of July
  • First harvests: yarrow

Instant PDF download. No spam, unsubscribe any time.

Achillea millefolium (Yarrow) is a tough, drought-tolerant native perennial with aromatic finely-divided foliage and broad flat-topped flower clusters that serve as a landing platform for hundreds of beneficial insect species. Available in white (the species type) and a wide range of cultivars spanning yellow, gold, pink, salmon, and deep red. Spreads by rhizome to form ground-covering colonies; blooms from late spring through midsummer with reblooming into fall if deadheaded. Exceptional in hot, dry sites where other perennials fail.

Marshall County, Kentucky is in USDA Zone 7a. The average last spring frost is April 3 and the first fall frost is November 1, giving you a growing season of approximately 212 days.

At an elevation of 1,550 feet, Marshall County receives approximately 42.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Yarrow during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Marshall County, KY (Zone 7a) Long season
212 days
Last Spring Frost April 3
212 growing days
First Fall Frost November 1

Marshall County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7.1

Drainage

Well Drained

Yarrow Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Start indoors: Jan 21 Transplant: Apr 1 🌸 Bloom: Jun 3 – Oct 14
Recommended (50%) ✓ Fits season (9 days to spare)
Start indoors: Jan 30 Transplant: Apr 10 🌸 Bloom: Jun 12 – Oct 23
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Feb 14 Transplant: Apr 25 🌸 Bloom: Jun 27 – Nov 7

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 Marshall County

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

Soil pH

Your soil pH (5.5–7.1) overlaps with Yarrow's range (5.5–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Marshall County is excellent for Yarrow — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Yarrow.

How to Plant Yarrow

18"
Between Plants
24"
Between Rows

Succession Planting Yarrow

4
successive plantings in your 212-day season

Sow every 6.9 weeks. Last sowing by Aug 03 to harvest before frost.

Yarrow Water Budget

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

Water stress score is 6/10 — 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 3.6" 0" ❄️ Dormant
Feb 4" 0" ❄️ Dormant
Mar 4" 0" ❄️ Dormant
Apr 2.2" 2.9" 0" ✅ Rainfall sufficient
May 2.2" 3.2" 0" ✅ Rainfall sufficient
Jun 2.2" 3.6" 0" ✅ Rainfall sufficient
Jul 2.2" 5" 0" ✅ Rainfall sufficient
Aug 2.2" 4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.5" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 2.2" 3" 0" ✅ Rainfall sufficient
Dec 3.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Marshall County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~1,256 GDD — county provides 3,551 GDD Excellent fit

Yarrow Planting Timeline — Marshall County, KY

Yarrow Planting Calendar

Activity When Date Range
Start Indoors January 30 Jan 30 – Feb 13
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow April 3 Apr 3 – Apr 24
Bloom June 12 Jun 12 – Oct 23

· 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

212 days in Marshall County

Growing Tips for Yarrow in Marshall County

Direct sow Yarrow outdoors after April 03 in Marshall 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

Start seeds indoors 8–10 weeks before last frost; seeds need light for germination — press onto soil surface, do not cover. Direct sow after last frost or divide established clumps in spring or fall. Thrives in poor, well-drained soil — rich soil and high fertility cause floppy stems and reduce flower count. Avoid overwatering; excellent drought tolerance once established. Deadhead spent clusters to encourage rebloom. Divide every 2–3 years to prevent center die-out and control spread. Year 2+ plants bloom most heavily; first-year plants may produce limited flowers. Dried flowers retain color well for arrangements.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Yarrow in Marshall County, KY?

Marshall County is in Zone 7a with an average last frost of April 3. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.

What planting zone is Marshall County, KY?

Marshall County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 3 and first fall frost is November 1.

When should I plant Yarrow in Marshall County County, ?

In Marshall County County, , plant Yarrow after the last frost (around April 3) and before the first frost (around November 1). Best results when soil holds above 50°F.

What growing zone is Marshall County County, for Yarrow?

Marshall County County sits in USDA Zone 7a. Yarrow grows reliably in zones 3a through 9b, so it's a good fit here.

Can Yarrow grow in Marshall County County's climate?

Yes — Yarrow grows well in Marshall County County's temperate climate. Marshall County County averages a 212-day frost-free season, with last frost around April 3 and first frost around November 1.

🌱

Your Marshall County Garden Planner — Free

A 22-page printable planner built for Marshall County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.