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When to Plant Sunflower in Hudson County, NJ

Hudson County, New Jersey Zone 7b June

Top priorities for Hudson County, New Jersey gardeners in June

June is a pivotal month for Hudson County, New Jersey gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost March 29
Avg. first frost November 12
Soil temp (4") 76°F
Watering Low
Pest pressure High
Daylight 14.9 hrs
  1. Collect sunflower at their peak

    If you can't use it all right away, check the food-preservation section of your planner.

Get ahead of July
  • First harvests: sunflower

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Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Hudson County, New Jersey is in USDA Zone 7b. 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 1,026 feet, Hudson County receives approximately 47.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Sunflower during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Hudson County, NJ (Zone 7b) Long season
228 days
Last Spring Frost March 29
228 growing days
First Fall Frost November 12

Hudson County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.8

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Mar 4 Transplant: Mar 25 🌸 Bloom: Jun 17 – Oct 7
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Mar 8 Transplant: Mar 29 🌸 Bloom: Jun 21 – Oct 11
Safe Start (90%) ✓ Fits season (41 days to spare)
Start indoors: Mar 19 Transplant: Apr 9 🌸 Bloom: Jul 2 – Oct 22

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 Hudson County

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

Soil pH

Your soil pH (4.8–6.8) is more acidic than Sunflower prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Hudson County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.7%). Annual compost additions will help Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

3
successive plantings in your 228-day season

Sow every 8 weeks. Last sowing by Aug 04 to harvest before frost.

Sunflower Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Sunflower

Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 2.2" 3.7" 0" ✅ Rainfall sufficient
Apr 2.2" 4.1" 0" ✅ Rainfall sufficient
May 2.2" 4.4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.2" 0" ✅ Rainfall sufficient
Jul 2.2" 4.5" 0" ✅ Rainfall sufficient
Aug 2.2" 4.3" 0" ✅ Rainfall sufficient
Sep 2.2" 4.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3.4" 0" ✅ Rainfall sufficient
Nov 2.2" 3.8" 0" ✅ Rainfall sufficient
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Hudson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sunflower 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.

Sunflower needs ~1,488 GDD — county provides 3,990 GDD Excellent fit

Sunflower Planting Timeline — Hudson County, NJ

Sunflower Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors March 29 Mar 29 – Apr 12
Direct Sow March 29 Mar 29 – Apr 19
Bloom June 21 Jun 21 – Oct 11

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7b

📆 Growing Season

228 days in Hudson County

Growing Tips for Sunflower in Hudson County

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

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

General growing tips

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Hudson County, NJ?

Hudson County is in Zone 7b with an average last frost of March 29. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hudson County, NJ?

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

🌱

Your Hudson County Garden Planner — Free

A 22-page printable planner built for Hudson County (Zone 7b). 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 Hudson County, NJ. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.