Sunflower

Basic Information

Seed Number

69

Seed Name

Sunflower

Variety

American Giant

Category

Flower

Plant Family

Asteraceae

Plant Type

American Giant hybrid sunflower (Helianthus annuus)

Planting Method

Direct Sow

Seed Status

In Seed Bank

Created

2026-08-14 00:50:34

Updated

2026-08-19 15:35:29

Planting Information

Start Planting Date

May 6

Last Recommended Planting Date

Jun 15

Plantable Months

May, June

Indoor Start

Not recorded

Direct Sow

May 6 – Jun 15

Transplant

Not Recommended

Indoor Start Weeks Before Frost

Not Recommended

Transplant Weeks After Frost

Not Recommended

Germination Days

14–21 days

Harvest/Maturity

120 days to bloom

Succession Planting

Not recorded

Growing Conditions

Ideal Soil Temperature

60°F+

Planting Depth

1 in

Plant Spacing

24 in

Row Spacing

30-36 in

Thin-To Spacing

24 in

Sun Requirements

Full sun

Water Needs

1-2 in/week; water deeply to encourage strong root development

Soil Preference

Fertile, well-drained soil; adequate fertility and consistent moisture support maximum height

Minimum Container Size

18+ in container

Plant Height

12-16 ft

Perennial/Biennial Status

Annual

Container Friendly

Yes

Trellis/Support Needed

No

Frost Tolerant

No

Heat Tolerant

Yes

Drought Tolerant

Yes

Pollinator Friendly

Yes

Medicinal

No

Garden Uses

Companion Planting

Storage

Seed Source/Brand

MSU Extension; Detroit frost dates; Almanac Detroit

Packet Year

Not recorded

Quantity Notes

Not recorded

Purchase Date

Not recorded

Expiration Year

Not recorded

Storage Box

Not recorded

Container

Not recorded

Envelope

Not recorded

Row

Not recorded

Slot

Not recorded

Storage Notes

Not recorded

Notes

Original Planting Method: Direct sow
Outdoor / Direct Sow / Transplant Window: May 10 – Jul 10
Days to Harvest / Bloom: 60–100 days to bloom
Container Friendly: Dwarf yes; giants need ground/large pots
Medicinal / Herbal Use: Seeds useful; pollinator support
Succession / Reusable Notes: Succession sow for blooms. Tall types need wind protection.
Zone 6B Notes: Direct sow after frost.
Companion Plants: Cucumbers, squash, pumpkins, melons, corn, pollinator flowers, clover
Avoid Planting Near / Watch Outs: Potatoes; may shade small crops
Sources: MSU Extension: https://www.canr.msu.edu/resources/garden_planning_calendar | Detroit frost dates: https://www.ufseeds.com/vegetable-planting-calendar-detroit-michigan.html | Almanac Detroit: https://www.almanac.com/gardening/planting-calendar/MI/Detroit

[[RESEARCH ENRICHMENT START]]
Zone 6B: Plant very soon after the May 5 frost date because American Giant requires a long growing season and may need around 120 days to bloom.
Germination: Ferry-Morse lists 14-21 days to germination. Sow after frost in warm soil.
Harvest: Primarily grown for its giant ornamental blooms and exceptional height. Mature heads may also be left for wildlife.
Seed Saving: American Giant is sold as an F1 hybrid. Saved seed will not reliably reproduce the original American Giant hybrid characteristics.
Special Care: Can reach 12-16 feet tall. Choose a wind-protected site and provide deep, consistent watering. Despite the extreme height, the cultivar is bred for strong stalks.
Research Source: Ferry-Morse — https://ferrymorse.com/products/sunflower-american-giant-hybrid-seeds — American Giant Hybrid identity, 12-16 foot height, 14-21 day germination, full sun, container size and water needs
Research Source: Urban Farmer — https://www.ufseeds.com/product/american-giant-f1-sunflower-seeds/SUAG.html — F1 hybrid status and approximately 120-day bloom maturity
[[RESEARCH ENRICHMENT END]]