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When to plant Sunflower in Worcester County, MA

Spring Sunflower in Worcester County goes in May 1–May 22, once nighttime temps stop dipping near freezing.

When to Plant Sunflower in Worcester County, MA

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.

Worcester County, Massachusetts is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 17, giving you a growing season of approximately 176 days.

At an elevation of 972 feet, Worcester County receives approximately 38 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Sunflower during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Worcester County, MA (Zone 6a) Moderate season
176 days
Last Spring Frost April 24
176 growing days
First Fall Frost October 17

Worcester County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.3

Drainage

Well Drained

Monthly Watering Guide for Sunflower

Sunflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 2.3" 0" ❄️ Dormant
Feb 2.6" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 3" 1.3" 💧 Light watering
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.3" 1" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 3.3" 0" ❄️ Dormant
Dec 2.9" 0" ❄️ Dormant

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

Sunflower Planting Timeline — Worcester County, MA

Sunflower Planting Calendar

Activity When Date Range
Start Indoors April 3 Apr 3 – Apr 17
Transplant Outdoors May 1 May 1 – May 15
Direct Sow May 1 May 1 – May 22
Bloom July 24 Jul 24 – Oct 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

176 days in Worcester County

Growing Tips for Worcester County

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 Worcester County, MA?

Worcester County is in Zone 6a with an average last frost of April 24. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Worcester County, MA?

Worcester County, Massachusetts is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 17.

When should I plant Sunflower in Worcester County, MA?

In Worcester County, MA, plant Sunflower after the last frost (around April 24) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Worcester County, MA for Sunflower?

Worcester County sits in USDA Zone 6a. Sunflower grows reliably in zones 2a through 11b, so it's a good fit here.

Can Sunflower grow in Worcester County's climate?

Yes — Sunflower grows well in Worcester County's temperate climate. Worcester County averages a 176-day frost-free season, with last frost around April 24 and first frost around October 17.

🌱

Your Worcester County Garden Planner — Free

A 22-page printable planner built for Worcester County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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