Blog

When to Plant Mint in Ferry County, WA

Mint is a vigorous perennial herb with refreshing, aromatic leaves used in teas, cocktails, and cooking. It spreads aggressively by underground runners.

Ferry County, Washington is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is September 24, giving you a growing season of approximately 137 days.

At an elevation of 3,990 feet, Ferry County receives approximately 18.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Mint to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Mint successfully. Mulch heavily to conserve soil moisture.

Ferry County, WA (Zone 5b) Short season
137 days
Last Spring Frost May 10
137 growing days
First Fall Frost September 24

Ferry County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.4

Drainage

Well Drained

Monthly Watering Guide for Mint

Mint needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Mint Needs Rainfall You Supplement Action
Jan โ€” 2.8" 0" โ„๏ธ Dormant
Feb โ€” 2.2" 0" โ„๏ธ Dormant
Mar โ€” 1.7" 0" โ„๏ธ Dormant
Apr โ€” 1.2" 0" โ„๏ธ Dormant
May 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
Jun 4.3" 0.7" 3.6" ๐Ÿšฟ Regular watering
Jul 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Aug 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Sep 4.3" 0.7" 3.6" ๐Ÿšฟ Regular watering
Oct โ€” 1.4" 0" โ„๏ธ Dormant
Nov โ€” 2.5" 0" โ„๏ธ Dormant
Dec โ€” 3.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Ferry County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Mint Planting Timeline โ€” Ferry County, WA

Mint Planting Calendar

Activity When Date Range
Transplant Outdoors May 17 May 17 โ€“ May 31
Harvest July 19 Jul 19 โ€“ Sep 27

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

High โ€” keep soil consistently moist

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

137 days in Ferry County

Growing Tips for Ferry County

Always grow mint in containers or with underground barriers to control spreading. Harvest regularly to keep plants compact. Cut plants back in late summer for a fresh fall flush.

Companion Planting

Good Companions

Avoid Planting Near

  • Parsley

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mint in Ferry County, WA?

Ferry County is in Zone 5b with an average last frost of May 10. Plan your Mint planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ferry County, WA?

Ferry County, Washington is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is September 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ferry County gardeners in Zone 5b 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 Ferry County, WA. Local conditions may vary. Last updated: April 2026.