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When to plant Mint in Park County, MT

Park County sits in cold Zone 5a. Plant Mint May 31–June 14 for the single annual harvest; the September 20 first frost closes the window.

When to Plant Mint in Park County, MT

Mint

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

Park County, Montana is in USDA Zone 5a. The average last spring frost is May 24 and the first fall frost is September 20, giving you a growing season of approximately 119 days.

At an elevation of 6,994 feet, Park County receives approximately 22.2 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Mint to ensure they mature before fall.

Park County, MT (Zone 5a) Short season
119 days
Last Spring Frost May 24
119 growing days
First Fall Frost September 20

Park County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Mint Planting Timeline — Park County, MT

Mint Planting Calendar

Activity When Date Range
Transplant Outdoors May 31 May 31 – Jun 14
Harvest August 2 Aug 2 – Oct 11

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Transplant Outdoors
June Transplant Outdoors
July
August Harvest
September Harvest
October Harvest
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

High — keep soil consistently moist

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

119 days in Park County

Growing Tips for Park 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 Park County, MT?

Park County is in Zone 5a with an average last frost of May 24. Plan your Mint planting based on this frost date — see the calendar above for exact timing.

What planting zone is Park County, MT?

Park County, Montana is in USDA Hardiness Zone 5a. The average last spring frost is May 24 and first fall frost is September 20.

When should I plant Mint in Park County, MT?

In Park County, MT, plant Mint after the last frost (around May 24) and before the first frost (around September 20). Best results when soil holds above 50°F.

What growing zone is Park County, MT for Mint?

Park County sits in USDA Zone 5a. Mint grows reliably in zones 3a through 10b, so it's a good fit here.

Can Mint grow in Park County's climate?

Yes — Mint grows well in Park County's temperate climate. Park County averages a 119-day frost-free season, with last frost around May 24 and first frost around September 20.

🌱

Your Park County Garden Planner — Free

A 22-page printable planner built for Park County (Zone 5a). 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 Park County, MT. Local conditions may vary. Last updated: June 2026.

Sources & credits

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