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When to Plant Jostaberry in St. Mary's County, MD

St. Mary's County, Maryland Zone 8a May

Top priorities for St. Mary's County, Maryland gardeners in May

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Avg. last frost April 5
Avg. first frost November 4
Soil temp (4") 68°F
Watering Low
Pest pressure Moderate
Daylight 14.1 hrs

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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.

St. Mary's County, Maryland is in USDA Zone 8a. The average last spring frost is April 5 and the first fall frost is November 4, giving you a growing season of approximately 213 days.

At an elevation of 156 feet, St. Mary's County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Jostaberry during the growing season.

St. Mary's County, MD (Zone 8a) Long season
213 days
Last Spring Frost April 5
213 growing days
First Fall Frost November 4
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St. Mary's County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 18
Recommended (50%) ✓ Fits season
Transplant: Apr 26
Safe Start (90%) ✓ Fits season
Transplant: May 17

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 St. Mary's County

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

Soil pH

Your soil pH (5.5–6.9) overlaps with Jostaberry's range (6.0–6.5), though not a perfect match.

Soil Texture

The silt loam soil in St. Mary's County is excellent for Jostaberry — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Jostaberry.

How to Plant Jostaberry

48"
Between Plants
72"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 344 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 3.1" 0" ❄️ Dormant
Feb 2.6" 0" ❄️ Dormant
Mar 3.3" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 4.3" 2.7" 1.6" 💧 Light watering
Dec 2.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in St. Mary's 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 needs ~17,338 GDD — county provides 4,047 GDD May not mature

Jostaberry Planting Timeline — St. Mary's County, MD

Jostaberry Planting Calendar

Activity When Date Range
Transplant Outdoors April 26 Apr 26 – May 10

· 48" apart · Rows 72" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 6–6.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

213 days in St. Mary's County

Growing Tips for Jostaberry in St. Mary's County

Direct sow Jostaberry outdoors after April 05 in St. Mary's County when soil has warmed and frost danger has passed.

Your 213.0-day growing season in St. Mary's 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 →

Frequently Asked Questions

When should I plant Jostaberry in St. Mary's County, MD?

St. Mary's County is in Zone 8a with an average last frost of April 5. Plan your Jostaberry planting based on this frost date — see the calendar above for exact timing.

What planting zone is St. Mary's County, MD?

St. Mary's County, Maryland is in USDA Hardiness Zone 8a. The average last spring frost is April 5 and first fall frost is November 4.

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Your St. Mary's County Garden Planner — Free

A 24-page printable planner built for St. Mary's County (Zone 8a). 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 St. Mary's County, MD. 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.