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When to Plant Echinacea in Union County, NJ

Echinacea (purple coneflower) is a native prairie perennial valued for its immune-supporting properties and beautiful daisy-like flowers that attract pollinators.

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 Echinacea 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) ✗ May not fit
Transplant: Apr 1 🍅 Harvest: Aug 5 – Nov 11
Recommended (50%) ✗ May not fit
Transplant: Apr 5 🍅 Harvest: Aug 9 – Nov 15
Safe Start (90%) ✓ Fits season (6 days to spare)
Transplant: Apr 16 🍅 Harvest: Aug 20 – Nov 26

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 Union County

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

Soil pH

Your soil pH (4.8โ€“6.5) is more acidic than Echinacea prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Union County is excellent for Echinacea โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Echinacea prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Echinacea.

How to Plant Echinacea

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Echinacea needs ~2,962 GDD — county provides 4,503 GDD Excellent fit

Echinacea Planting Timeline โ€” Union County, NJ

Echinacea Planting Calendar

Activity When Date Range
Transplant Outdoors April 5 Apr 5 โ€“ Apr 19
Harvest August 9 Aug 9 โ€“ Nov 15

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

120โ€“180 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

228 days in Union County

Growing Tips for Echinacea in Union County

Direct sow Echinacea outdoors after March 29 in Union County when soil has warmed and frost danger has passed.

Common pests for Echinacea in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 8-10 weeks before last frost or direct sow in fall for spring germination. Seeds need cold stratification. Deadhead to prolong blooming or leave seed heads for birds.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Echinacea in Union County, NJ?

Union County is in Zone 7a with an average last frost of March 29. Plan your Echinacea 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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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.