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When to Plant Sunflower in Rhode Island

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.

Rhode Island spans USDA hardiness zones 6b, 7a (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

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Click your county for exact Sunflower planting dates based on your local frost dates.

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Sunflower Planting Calendar for Rhode Island

Zone 6b ~205 day growing season · Full guide →

Last frost: April 3 · First frost: October 25 · 205 day season

Activity When Date Range
Start Indoors March 13 Mar 13 – Mar 27
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow April 3 Apr 3 – Apr 24
Bloom June 26 Jun 26 – Sep 25
Zone 7a ~221 day growing season · Full guide →

Last frost: March 25 · First frost: November 1 · 221 day season

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow March 25 Mar 25 – Apr 15
Bloom June 17 Jun 17 – Sep 23

Growing Tips for Rhode Island

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.

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Frequently Asked Questions

When should I plant Sunflower in Rhode Island?

Planting dates for Sunflower in Rhode Island depend on your USDA zone. Rhode Island spans zones 6b, 7a. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Rhode Island for planting?

Rhode Island contains USDA hardiness zones 6b, 7a. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Last updated: June 2026.