When to plant Jostaberry in Keweenaw County, MI
Keweenaw County's short 135-day growing season means one Jostaberry planting between June 9 and June 23. No fall crop in Zone 5b.
When to Plant Jostaberry in Keweenaw County, MI
What to do in June
A quick June briefing for Keweenaw County, Michigan gardeners — what's urgent, what's next, and what can wait.
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Move jostaberry from tray to bed
Your last frost (May 19) has passed. These warm-season crops can handle outdoor soil now.
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.
Keweenaw County, Michigan is in USDA Zone 5b. The average last spring frost is May 19 and the first fall frost is October 1, giving you a growing season of approximately 135 days.
At an elevation of 1,035 feet, Keweenaw County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Jostaberry to ensure they mature before fall.
Keweenaw County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.9
Drainage
Well Drained
Jostaberry Planting Risk Windows
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 Keweenaw County
How your county's soil matches Jostaberry's growing requirements.
Soil pH
Your soil pH (6.1–6.9) overlaps with Jostaberry's range (6.0–6.5), though not a perfect match.
Soil Texture
The silt loam soil in Keweenaw County is excellent for Jostaberry — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.0%) — Jostaberry will thrive.
How to Plant Jostaberry
Jostaberry Water Budget
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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | — | 3.7" | 0" | ❄️ Dormant |
| May | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jun | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Oct | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Keweenaw County). 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 Planting Timeline — Keweenaw County, MI
Jostaberry Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 9 | Jun 9 – Jun 23 |
· 48" apart · Rows 72" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| 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: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
135 days in Keweenaw County
Growing Tips for Jostaberry in Keweenaw County
Direct sow Jostaberry outdoors after May 19 in Keweenaw County when soil has warmed and frost danger has passed.
Your 135.0-day growing season in Keweenaw County 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 →
Jostaberry in Other Locations
Frequently Asked Questions
When should I plant Jostaberry in Keweenaw County, MI?
Keweenaw County is in Zone 5b with an average last frost of May 19. Plan your Jostaberry planting based on this frost date — see the calendar above for exact timing.
What planting zone is Keweenaw County, MI?
Keweenaw County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 19 and first fall frost is October 1.
When should I plant Jostaberry in Keweenaw County, MI?
In Keweenaw County, MI, plant Jostaberry after the last frost (around May 19) and before the first frost (around October 1). Best results when soil holds above 50°F.
What growing zone is Keweenaw County, MI for Jostaberry?
Keweenaw County sits in USDA Zone 5b. Jostaberry grows reliably in zones 3a through 8b, so it's a good fit here.
Can Jostaberry grow in Keweenaw County's climate?
Yes — Jostaberry grows well in Keweenaw County's temperate climate. Keweenaw County averages a 135-day frost-free season, with last frost around May 19 and first frost around October 1.
Your Keweenaw County Garden Planner — Free
A 22-page printable planner built for Keweenaw County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.