When to Plant Sunflower in Gloucester County, NJ
Gloucester County, New Jersey gardeners: here's your June plan
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Gloucester County, New Jersey.
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It's harvest week for sunflower
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
A few tasks this June that'll pay off in July
- First harvests: sunflower
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.
Gloucester County, New Jersey is in USDA Zone 7b. The average last spring frost is April 5 and the first fall frost is November 12, giving you a growing season of approximately 221 days.
At an elevation of 735 feet, Gloucester County receives approximately 49.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94°F, providing good warmth for Sunflower during the growing season.
Gloucester County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.8
Drainage
Well Drained
Sunflower Planting Risk Windows
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 Gloucester County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (5.2–6.8) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Gloucester County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.5%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 04 to harvest before frost.
Sunflower Water Budget
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 | — | 3.7" | 0" | ❄️ Dormant |
| Feb | — | 3" | 0" | ❄️ Dormant |
| Mar | — | 4.5" | 0" | ❄️ Dormant |
| Apr | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 5.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Gloucester 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 Planting Timeline — Gloucester County, NJ
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | April 5 | Apr 5 – Apr 19 |
| Direct Sow | April 5 | Apr 5 – Apr 26 |
| Bloom | June 28 | Jun 28 – Oct 18 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| 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: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
221 days in Gloucester County
Growing Tips for Sunflower in Gloucester County
Direct sow Sunflower outdoors after April 05 in Gloucester 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
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Gloucester County, NJ?
Gloucester County is in Zone 7b with an average last frost of April 5. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gloucester County, NJ?
Gloucester County, New Jersey is in USDA Hardiness Zone 7b. The average last spring frost is April 5 and first fall frost is November 12.
Your Gloucester County Garden Planner — Free
A 22-page printable planner built for Gloucester 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.