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When to plant Yarrow in Power County, ID

In Power County, Yarrow is a single-season spring crop — there's no second fall window. Plant May 11–June 1 for an 60–90-day harvest, finishing well before the September 30 first frost.

When to Plant Yarrow in Power County, ID

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.

Power County, Idaho is in USDA Zone 6a. The average last spring frost is May 11 and the first fall frost is September 30, giving you a growing season of approximately 142 days.

At an elevation of 6,609 feet, Power County receives approximately 14 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Yarrow during the growing season. With low rainfall, drip irrigation is essential for growing Yarrow successfully. Mulch heavily to conserve soil moisture.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Power County, ID (Zone 6a) Short season
142 days
Last Spring Frost May 11
142 growing days
First Fall Frost September 30

Power County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Yarrow Planting Timeline — Power County, ID

Yarrow Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 – Mar 23
Transplant Outdoors May 18 May 18 – Jun 1
Direct Sow May 11 May 11 – Jun 1
Bloom July 27 Jul 27 – Nov 16

· 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

142 days in Power County

Growing Tips for Power County

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 Power County, ID?

Power County is in Zone 6a with an average last frost of May 11. Plan your Yarrow planting based on this frost date — see the calendar above for exact timing.

What planting zone is Power County, ID?

Power County, Idaho is in USDA Hardiness Zone 6a. The average last spring frost is May 11 and first fall frost is September 30.

When should I plant Yarrow in Power County, ID?

In Power County, ID, plant Yarrow after the last frost (around May 11) and before the first frost (around September 30). Best results when soil holds above 50°F.

What growing zone is Power County, ID for Yarrow?

Power County sits in USDA Zone 6a. Yarrow grows reliably in zones 3a through 9b, so it's a good fit here.

Can Yarrow grow in Power County's climate?

Yes — Yarrow grows well in Power County's temperate climate. Power County averages a 142-day frost-free season, with last frost around May 11 and first frost around September 30.

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Your Power County Garden Planner — Free

A 22-page printable planner built for Power County (Zone 6a). 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 Power County, ID. Local conditions may vary. Last updated: July 2026.

Sources & credits

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