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When to Plant Serviceberries in Union County, NJ

Serviceberries (saskatoons) are attractive native shrubs or small trees producing sweet, blueberry-like fruits. They have beautiful spring flowers and vibrant fall color.

Union County, New Jersey is in USDA Zone 7a. The average last spring frost is March 29 and the first fall frost is November 12, giving you a growing season of approximately 228 days.

At an elevation of 814 feet, Union County receives approximately 49.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93ยฐF, providing good warmth for Serviceberries during the growing season.

Union County, NJ (Zone 7a) Long season
228 days
Last Spring Frost March 29
228 growing days
First Fall Frost November 12

Union County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 15
Recommended (50%) ✓ Fits season
Transplant: Apr 19
Safe Start (90%) ✓ Fits season
Transplant: Apr 30

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Serviceberries needs ~18,022 GDD — county provides 4,503 GDD May not mature

Serviceberries Planting Timeline โ€” Union County, NJ

Serviceberries Planting Calendar

Activity When Date Range
Transplant Outdoors April 19 Apr 19 โ€“ May 3

ยท 120" apart ยท Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

730โ€“1095 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 7a

Growing Season

228 days

Growing Tips for Union County

Plant in well-drained soil. Minimal pruning needed beyond removing dead wood. Protect fruit from birds with netting. Berries ripen in early summer and are excellent fresh or in pies.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Serviceberries in Union County, NJ?

Union County is in Zone 7a with an average last frost of March 29. Plan your Serviceberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Union County, NJ?

Union County, New Jersey is in USDA Hardiness Zone 7a. The average last spring frost is March 29 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Union County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Union County, NJ. Local conditions may vary. Last updated: April 2026.