my LocalPlanting

When to Plant Dahlia in Fortescue, New Jersey (08321)

Location

Fortescue, New Jersey

ZIP Code

08321

USDA Zone

7b

Last Frost

Sunday, April 5, 2026

📅 Your 2026 Planting Dates

Start Seeds Indoors

Sunday, February 22, 2026

Transplant Outdoors

Sunday, April 12, 2026

Based on last frost Sunday, April 5, 2026 · Zone 7b

Pro tip: Start Dahlia seeds indoors 6 weeks before your last frost date, then transplant outdoors around Sunday, April 12, 2026.

🌿 Plant Details

Scientific Name Dahlia pinnata
Days to Maturity 90 days
Mature Height 18-60"
Spread 18"

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Regular (1-2 inches/week)

↔️

Spacing

18" apart

🌱

Planting Depth

4" deep

Seeds typically germinate in 7-14 days

Ready to Plant Dahlia in Fortescue?

Get your seeds now so they're ready by Sunday, February 22, 2026.

* Affiliate links — we may earn a small commission at no extra cost to you.

🤝 Good Companions

MarigoldBasilCosmos
🤝

Full Companion Planting Guide for Dahlia

See which plants help Dahlia thrive, which to keep away, and raised bed layout tips →

🛠️ Supplies You'll Need

* Affiliate links — we may earn a small commission at no extra cost to you.

🌾 Seed Saving Guide

🟡 Moderate
⚠️ Many varieties are F1 hybrid — look for OP/heirloom types

When to Harvest Seed

Allow seed pods (behind the flower) to dry on the plant in fall.

Processing

Remove dried seed pods, extract flat seeds, dry 1 week in an open envelope.

Seed Viability

Up to 2 years when stored cool, dark, and dry.

Pro Tip

Dahlia seeds do not grow true to the parent — each seedling is a unique hybrid. Propagate named varieties by tuber division.

🪴

Raised Bed Planting Guides

A 4×8 bed fits 14 plants of Dahlia. See plant counts, spacing grids, and companion pairings for every bed size →

Frequently Asked Questions

When should I plant Dahlia in Fortescue, New Jersey? +

In Fortescue (Zone 7b), start Dahlia seeds indoors around Sunday, February 22, 2026 and transplant outdoors around Sunday, April 12, 2026.

What is the last frost date for Fortescue, New Jersey? +

The average last spring frost date for Fortescue, New Jersey (ZIP 08321) is around Sunday, April 5, 2026. This is based on NOAA climate normals for USDA Zone 7b.

How long does Dahlia take to grow? +

Dahlia typically matures in about 90 days from transplanting. In Fortescue, that means you can expect harvest around Sunday, April 12, 2026 plus 90 days.

Should I start Dahlia indoors or direct sow in New Jersey? +

Dahlia should be started indoors 6 weeks before your last frost date. In Fortescue, that means starting around Sunday, February 22, 2026.

Other Plants for Fortescue

Growing Dahlia in Zone 7b

Dahlia (Dahlia pinnata) is a popular garden vegetable. In Fortescue, New Jersey, which is in USDA Hardiness Zone 7b, you should start seeds indoors around Sunday, February 22, 2026.

Your average last frost date is Sunday, April 5, 2026. Plan to transplant your Dahlia seedlings outdoors around Sunday, April 12, 2026, about 1 weeks after your last frost date.