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When to Plant Sunflower in USDA Zone 6a

Zone 6a Zone 6a May

What to do in May

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 27
Avg. first frost October 16
  1. Set out sunflower seedlings

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

  2. Outdoor sowing time: sunflower

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

To set up a strong June, finish these tasks
  • Starting indoors: sunflower
Get the full Zone 6a Garden Planner — free →

Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.

In Zone 6a, the average last spring frost is around April 10 and the first fall frost is around October 20, giving you a growing season of approximately 193 days.

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Zone 6a Moderate season
193 days
Last Spring Frost April 10
193 growing days
First Fall Frost October 20

Sunflower Planting Timeline — Zone 6a

Where Is USDA Zone 6a?

The map below highlights the states that contain Zone 6a. Click any state to see the Sunflower planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Sunflower Planting Calendar — Zone 6a

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 17 Apr 17 – May 8
Harvest July 3 Jul 3 – Aug 21

Plant 1" deep · 18" apart · Rows 30" apart

Month-by-Month Timeline

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

Free Zone 6a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6a with start dates, transplant windows, and harvest times.

Instant PDF download. No spam, unsubscribe any time.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

Days to Maturity

70–100 days

Soil pH

6 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

193 days (Zone average)

Planting Specifications

Planting Depth1 inches
Plant Spacing18 inches apart
Row Spacing30 inches between rows

Succession Planting Sunflower in Zone

3
successive plantings in Zone 's ~193-day season

Sow every 8 weeks for continuous harvest throughout the season.

Growing Tips for Sunflower in Zone

Zone has a short growing season (~193 days). Start Sunflower indoors early and use season-extension techniques like row covers and cold frames.

Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
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Saving Sunflower Seeds

Recommended for Your Garden

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

🏷️
Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Sunflower in Zone 6a?

In Zone 6a, plan your Sunflower planting around the average last frost date of April 10. Start seeds indoors around February 13. Direct sow outdoors around April 17. Transplant seedlings around April 24.

Can Sunflower grow in Zone 6a?

Yes, Sunflower can grow well in Zone 6a, hardy in USDA zones 2a through 11b. Zone 6a has a growing season of approximately 193 days, which is sufficient for Sunflower (70-100 days to maturity).

When can I harvest Sunflower in Zone 6a?

In Zone 6a, expect to harvest Sunflower from July 3 – August 21. Sunflower takes 70-100 days from planting to harvest.

What is the last frost date for Zone 6a?

The average last spring frost in Zone 6a is around April 10, and the first fall frost is around October 20. This gives a growing season of approximately 193 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Sunflower?

Good companion plants for Sunflower include Corn, Cucumber, Squash Summer. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Your Free Printable Garden Planner

A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: May 2026.

Sources & credits

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