When should I plant Sunflower in Zone 2a?

Start Sunflower seeds indoors around Apr 24. Transplant outdoors after May 22. Expect first harvest around Jul 26.

What is the last frost date for Zone 2a?

The average last spring frost date for Zone 2a is May 15. The first fall frost averages Sep 15, giving a 123-day growing season.

Can I grow Sunflower in Zone 2a?

Yes. Sunflower needs 90 days to harvest. Zone 2a has a 123-day growing season, which is sufficient. You can plant up to 2 successions.

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🌻 Growing Sunflower in Zone 2a

Zone 2a has harsh winters and a short growing season. Start Sunflower early indoors to maximize your harvest window. Last frost: May 15. First frost: Sep 15.

Planting Calendar

Indoor

Outdoor

Harvest

Apr 24Sep 15

Season: May 15 – Sep 15 (123 days) · Succession: plant every 2 weeks (up to 2x)

Zone2a

Last FrostMay 15

First FrostSep 15

Season Length123 days

Days to Harvest90

SunFull Sun

Frost ToleranceNone

Spacing1/sqft (12" apart)

When to Plant Sunflower in Zone 2a

Start Seeds Indoors: Apr 24

Start Sunflower seeds indoors around Apr 24 (3 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 7–14 days.

Transplant Outdoors: May 22

Transplant Sunflower seedlings outdoors after May 22. Wait until soil temperature reaches 55°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Jul 26

First harvest approximately Jul 26 (~65 days from transplant). Continue harvesting until first frost (Sep 15).

Companion Planting

✅ Cucumbers✅ Squash ✅ Corn✅ Beans

❌ Potatoes

Sunflower in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Sunflower Garden

Track Sunflower from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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