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When to Plant Mint in Weston County, WY

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

Weston County, Wyoming is in USDA Zone 4a. The average last spring frost is May 16 and the first fall frost is September 26, giving you a growing season of approximately 133 days.

At an elevation of 5,889 feet, Weston County receives approximately 20.7 inches of rainfall annually with predominantly loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Mint to ensure they mature before fall.

Weston County, WY (Zone 4a) Short season
133 days
Last Spring Frost May 16
133 growing days
First Fall Frost September 26

Weston County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 19 🍅 Harvest: Jul 21 – Sep 29
Recommended (50%) ✗ May not fit
Transplant: May 23 🍅 Harvest: Jul 25 – Oct 3
Safe Start (90%) ✗ May not fit
Transplant: Jun 5 🍅 Harvest: Aug 7 – Oct 16

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 Weston County

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

Soil pH

Your soil pH (6.7โ€“7.7) is more alkaline than Mint prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Weston County is excellent for Mint โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Mint.

How to Plant Mint

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Mint

2
successive plantings in your 133-day season

Sow every 6.9 weeks. Last sowing by Jun 28 to harvest before frost.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.7″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 66 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Mint

Mint needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Mint Needs Rainfall You Supplement Action
Jan โ€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.4" 0" โ„๏ธ Dormant
Mar โ€” 1.7" 0" โ„๏ธ Dormant
Apr โ€” 2.3" 0" โ„๏ธ Dormant
May 3" 2.3" 0.7" ๐Ÿ’ง Light watering
Jun 3" 1.5" 1.5" ๐Ÿšฟ Regular watering
Jul 3" 1.9" 1.1" ๐Ÿ’ง Light watering
Aug 3" 2.2" 0.8" ๐Ÿ’ง Light watering
Sep 3" 1.6" 1.4" ๐Ÿ’ง Light watering
Oct โ€” 1.9" 0" โ„๏ธ Dormant
Nov โ€” 1.2" 0" โ„๏ธ Dormant
Dec โ€” 1.1" 0" โ„๏ธ Dormant

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

Mint 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" โ€” every day above 50ยฐF 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.

Mint needs ~806 GDD — county provides 1,429 GDD Excellent fit

Mint Planting Timeline โ€” Weston County, WY

Mint Planting Calendar

Activity When Date Range
Transplant Outdoors May 23 May 23 โ€“ Jun 6
Harvest July 25 Jul 25 โ€“ Oct 3

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.7"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

133 days in Weston County

Growing Tips for Mint in Weston County

Direct sow Mint outdoors after May 16 in Weston County when soil has warmed and frost danger has passed.

General growing tips

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 Weston County, WY?

Weston County is in Zone 4a with an average last frost of May 16. Plan your Mint planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Weston County, WY?

Weston County, Wyoming is in USDA Hardiness Zone 4a. The average last spring frost is May 16 and first fall frost is September 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Weston County gardeners in Zone 4a 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 Weston County, WY. Local conditions may vary. Last updated: April 2026.