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When to plant Yarrow in White County, IL

In White County, plant Yarrow in spring between April 8 and April 29, once soil temps hold above 50°F. White County's last frost averages April 8, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between and — roughly 90 days before the first frost on October 27.

When to Plant Yarrow in White County, IL

White County, Illinois Zone 7a June

Your June planting checklist for White County, Illinois

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 8
Avg. first frost October 27
Soil temp (4") 74°F
Watering Moderate
Pest pressure High
Daylight 14.6 hrs
  1. Sow yarrow in trays indoors

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

  2. Harvest yarrow as they ripen

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

To set up a strong July, finish these tasks
  • First harvests: yarrow

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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.

White County, Illinois is in USDA Zone 7a. The average last spring frost is April 8 and the first fall frost is October 27, giving you a growing season of approximately 202 days.

At an elevation of 788 feet, White County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Yarrow during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
White County, IL (Zone 7a) Long season
202 days
Last Spring Frost April 8
202 growing days
First Fall Frost October 27

White County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7

Drainage

Well Drained

Yarrow Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Jan 29 Transplant: Apr 9 🌸 Bloom: Jun 11 – Oct 22
Recommended (50%) ✗ May not fit
Start indoors: Feb 4 Transplant: Apr 15 🌸 Bloom: Jun 17 – Oct 28
Safe Start (90%) ✓ Fits season (5 days to spare)
Start indoors: Feb 16 Transplant: Apr 27 🌸 Bloom: Jun 29 – Nov 9

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 White County

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

Soil pH

Your soil pH (5.8–7.0) is within Yarrow's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Yarrow will thrive.

How to Plant Yarrow

18"
Between Plants
24"
Between Rows

Succession Planting Yarrow

3
successive plantings in your 202-day season

Sow every 6.9 weeks. Last sowing by Jul 29 to harvest before frost.

Yarrow Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/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 1.1" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 2.2" 3.2" 0" ✅ Rainfall sufficient
May 2.2" 3.5" 0" ✅ Rainfall sufficient
Jun 2.2" 3.6" 0" ✅ Rainfall sufficient
Jul 2.2" 3.4" 0" ✅ Rainfall sufficient
Aug 2.2" 3.5" 0" ✅ Rainfall sufficient
Sep 2.2" 2.4" 0" ✅ Rainfall sufficient
Oct 2.2" 2.5" 0" ✅ Rainfall sufficient
Nov 2.1" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in White 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 ~1,031 GDD — county provides 2,777 GDD Excellent fit

Yarrow Planting Timeline — White County, IL

Yarrow Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 8 Apr 8 – Apr 29
Bloom June 17 Jun 17 – Oct 28

· 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
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: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

202 days in White County

Growing Tips for Yarrow in White County

Direct sow Yarrow outdoors after April 08 in White 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 White County, IL?

White County is in Zone 7a with an average last frost of April 8. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.

What planting zone is White County, IL?

White County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 8 and first fall frost is October 27.

When should I plant Yarrow in White County, IL?

In White County, IL, plant Yarrow after the last frost (around April 8) and before the first frost (around October 27). Best results when soil holds above 50°F.

What growing zone is White County, IL for Yarrow?

White 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 White County's climate?

Yes — Yarrow grows well in White County's temperate climate. White County averages a 202-day frost-free season, with last frost around April 8 and first frost around October 27.

🌱

Your White County Garden Planner — Free

A 22-page printable planner built for White 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.

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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 White County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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