Sunflower

Basic Information

Seed Number

193

Seed Name

Sunflower

Variety

Skyscraper

Category

Flower

Plant Family

Asteraceae

Plant Type

Giant annual 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

Jul 1

Plantable Months

May, June, July

Indoor Start

Not recorded

Direct Sow

May 6 – Jul 1

Transplant

Not Recommended

Indoor Start Weeks Before Frost

Not Recommended

Transplant Weeks After Frost

Not Recommended

Germination Days

7–10 days

Harvest/Maturity

75 days to bloom

Succession Planting

Not recorded

Growing Conditions

Ideal Soil Temperature

70°F+

Planting Depth

1/2-1 in

Plant Spacing

18-24 in

Row Spacing

24-36 in

Thin-To Spacing

18-24 in

Sun Requirements

Full sun

Water Needs

Water deeply during establishment and prolonged dry periods

Soil Preference

Loose, fertile, well-drained soil

Minimum Container Size

only in a very large/heavy pot; best in the ground

Plant Height

Up to 10-12 ft

Perennial/Biennial Status

Annual

Container Friendly

No

Trellis/Support Needed

Yes

Frost Tolerant

No

Heat Tolerant

Yes

Drought Tolerant

Yes

Pollinator Friendly

Yes

Medicinal

No

Garden Uses

Companion Planting

Storage

Seed Source/Brand

Hudson Valley Seed; Ferry-Morse; MSU Extension

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 after frost
Outdoor / Direct Sow / Transplant Window: May 10 – Jul 10
Days to Harvest / Bloom: About 70–90 days to bloom
Container Friendly: Possible only in a very large/heavy pot; best in the ground
Pollinator Friendly: Yes; excellent for bees and other pollinators
Medicinal / Herbal Use: Edible seed/bird seed use after maturity; mainly ornamental
Perennial?: No; annual
Succession / Reusable Notes: Succession sow every 2–3 weeks through early July for a longer bloom period.
Zone 6B Notes: Can reach around 10–12 ft; choose a sheltered full-sun location.
Companion Plants: Cucumbers, squash, pumpkins, melons, corn and other pollinator flowers
Avoid Planting Near / Watch Outs: Very tall plants can shade smaller crops and may need staking or wind protection.
Sources: Hudson Valley Seed: https://hudsonvalleyseed.com/products/skyscraper-sunflower | Ferry-Morse: https://ferrymorse.com/products/sunflower-skyscraper-seeds | MSU Extension: https://www.canr.msu.edu/resources/garden_planning_calendar

[[RESEARCH ENRICHMENT START]]
Zone 6B: Direct sow after frost and warm soil. Its tall growth means the plant should be positioned where it will not shade shorter crops.
Germination: Direct sow in warm soil and thin to provide substantial room for stalk development.
Harvest: Flowers can reach about 14 inches across. For edible seed, allow the head to mature and dry after petals fade and the back of the head yellows to brown.
Seed Saving: Skyscraper is an open-pollinated annual sunflower and can cross readily with nearby Helianthus annuus varieties.
Special Care: Because plants can reach 10-12 feet with very large flower heads, staking or planting along a sturdy fence is recommended.
Research Source: Gurney's — https://www.gurneys.com/products/skyscraper_sunflower_ — 75-day maturity, up-to-12-foot height, 14-inch flowers, pollinator value, edible seed and staking recommendation
Research Source: Ferry-Morse — https://ferrymorse.com/products/sunflower-skyscraper-seeds — Skyscraper identity and giant sunflower habit
[[RESEARCH ENRICHMENT END]]