Blog

When to Plant Yarrow in Benewah County, ID

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.

Benewah County, Idaho is in USDA Zone 6a. The average last spring frost is May 8 and the first fall frost is October 1, giving you a growing season of approximately 146 days.

At an elevation of 6,081 feet, Benewah County receives approximately 20.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, providing good warmth for Yarrow during the growing season.

Benewah County, ID (Zone 6a) Short season
146 days
Last Spring Frost May 8
146 growing days
First Fall Frost October 1

Benewah County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 6 🍅 Harvest: Aug 5 – Oct 21
Recommended (50%) ✗ May not fit
Transplant: May 15 🍅 Harvest: Aug 14 – Oct 30
Safe Start (90%) ✗ May not fit
Transplant: Jun 13 🍅 Harvest: Sep 12 – Nov 28

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.

Plant 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 โ€” consider drought-tolerant varieties and mulching

Yarrow needs ~1,838 GDD — county provides 2,555 GDD Excellent fit

Yarrow Planting Timeline โ€” Benewah County, ID

Yarrow Planting Calendar

Activity When Date Range
Transplant Outdoors May 15 May 15 โ€“ May 29
Harvest August 14 Aug 14 โ€“ Oct 30

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 โ€”
July โ€”
August Harvest
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

90โ€“120 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 6a

Growing Season

146 days

Growing Tips for Benewah County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Yarrow in Benewah County, ID?

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

What planting zone is Benewah County, ID?

Benewah County, Idaho is in USDA Hardiness Zone 6a. The average last spring frost is May 8 and first fall frost is October 1.

๐ŸŒฑ

Plan Your Garden with Confidence

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