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When to plant Jostaberry in Flathead County, MT

Flathead County sits in cold Zone 5a. Plant Jostaberry June 24–July 8 for the single annual harvest; the September 10 first frost closes the window.

When to Plant Jostaberry in Flathead County, MT

Jostaberry is a thornless hybrid of black currant and gooseberry, producing medium-sized, dark berries with a complex, tart-sweet flavor. It is vigorous and disease-resistant.

Flathead County, Montana is in USDA Zone 5a. The average last spring frost is June 3 and the first fall frost is September 10, giving you a growing season of approximately 99 days.

At an elevation of 6,233 feet, Flathead County receives approximately 20.7 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Jostaberry during the growing season.

Flathead County, MT (Zone 5a) Very short season
99 days
Last Spring Frost June 3
99 growing days
First Fall Frost September 10

Flathead County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Jostaberry Planting Timeline — Flathead County, MT

Jostaberry Planting Calendar

Activity When Date Range
Transplant Outdoors June 24 Jun 24 – Jul 8

· 48" apart · Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 6–6.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

99 days in Flathead County

Growing Tips for Flathead County

Plant in rich, well-drained soil. No special pruning required beyond removing old wood. Self-fertile but yields improve with a second bush. Berries ripen midsummer.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Jostaberry in Flathead County, MT?

Flathead County is in Zone 5a with an average last frost of June 3. Plan your Jostaberry planting based on this frost date — see the calendar above for exact timing.

What planting zone is Flathead County, MT?

Flathead County, Montana is in USDA Hardiness Zone 5a. The average last spring frost is June 3 and first fall frost is September 10.

When should I plant Jostaberry in Flathead County, MT?

In Flathead County, MT, plant Jostaberry after the last frost (around June 3) and before the first frost (around September 10). Best results when soil holds above 50°F.

What growing zone is Flathead County, MT for Jostaberry?

Flathead County sits in USDA Zone 5a. Jostaberry grows reliably in zones 3a through 8b, so it's a good fit here.

Can Jostaberry grow in Flathead County's climate?

Yes — Jostaberry grows well in Flathead County's temperate climate. Flathead County averages a 99-day frost-free season, with last frost around June 3 and first frost around September 10.

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Your Flathead County Garden Planner — Free

A 22-page printable planner built for Flathead 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 Flathead County, MT. Local conditions may vary. Last updated: July 2026.

Sources & credits

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