Blog

When to Plant Jostaberry in Wrangell City and Borough, AK

Wrangell City and Borough, Alaska Zone 7b May

Your May game plan for Wrangell City and Borough, Alaska

Each item below is timed to Wrangell City and Borough, Alaska's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 23
Avg. first frost October 20
Soil temp (4") 62°F
Watering High
Pest pressure Moderate
Daylight 16.1 hrs
  1. Time to transplant jostaberry

    Frost risk is low now in Wrangell City and Borough, Alaska. If you've been covering beds overnight, you can stop.

Instant PDF download. No spam, unsubscribe any time.

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.

Wrangell City and Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 23 and the first fall frost is October 20, giving you a growing season of approximately 180 days.

At an elevation of 1,533 feet, Wrangell City and Borough receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 59°F, so choose short-season varieties of Jostaberry to ensure they mature before fall.

Wrangell City and Borough, AK (Zone 7b) Moderate season
180 days
Last Spring Frost April 23
180 growing days
First Fall Frost October 20

Wrangell City and Borough Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 7
Recommended (50%) ✓ Fits season
Transplant: May 14
Safe Start (90%) ✓ Fits season
Transplant: Jun 2

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 Wrangell City and Borough

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

Soil pH

Your soil pH (5.1–6.5) is more acidic than Jostaberry prefers (6.0–6.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Wrangell City and Borough is excellent for Jostaberry — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Jostaberry.

Organic Matter

Organic matter is excellent (6.1%) — Jostaberry will thrive.

How to Plant Jostaberry

48"
Between Plants
72"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Jostaberry

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

Month Jostaberry Needs Rainfall You Supplement Action
Jan 1.9" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 1.1" 0" ❄️ Dormant
Apr 4.3" 1.1" 3.2" 🚿 Regular watering
May 4.3" 1.4" 2.9" 🚿 Regular watering
Jun 4.3" 2.9" 1.4" 💧 Light watering
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 6.2" 0" ✅ Rainfall sufficient
Sep 4.3" 5.4" 0" ✅ Rainfall sufficient
Oct 4.3" 4.8" 0" ✅ Rainfall sufficient
Nov 2.9" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Wrangell City and Borough). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Jostaberry 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" — every day above 50°F 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.

Jostaberry needs ~0 GDD — county provides 0 GDD May not mature

Jostaberry Planting Timeline — Wrangell City and Borough, AK

Jostaberry Planting Calendar

Activity When Date Range
Transplant Outdoors May 14 May 14 – May 28

· 48" apart · Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 6–6.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7b

📆 Growing Season

180 days in Wrangell City and Borough

Growing Tips for Jostaberry in Wrangell City and Borough

Direct sow Jostaberry outdoors after April 23 in Wrangell City and Borough when soil has warmed and frost danger has passed.

Your 180.0-day growing season in Wrangell City and Borough is tight for Jostaberry (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

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 Wrangell City and Borough, AK?

Wrangell City and Borough is in Zone 7b with an average last frost of April 23. Plan your Jostaberry planting based on this frost date — see the calendar above for exact timing.

What planting zone is Wrangell City and Borough, AK?

Wrangell City and Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 23 and first fall frost is October 20.

🌱

Your Wrangell City and Borough Garden Planner — Free

A 24-page printable planner built for Wrangell City and Borough (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Wrangell City and Borough, AK. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.