Helianthus is the botanical name for Sunflower
Helianthus Germination Information

Helianthus Seed Germination How to Sow Helianthus:

  • Can be sown indoors at 68-86° (will germinate over a wide temperature range)
  • Sow 2-3 weeks before planting out
  • Expect germination in 5-10 days
  • They can be sown outdoors after last frost, but remember: they are a favorite food of birds and rodents and may be eaten by them
  • When sowing seed outdoors, we recommend a maximum planting depth of 4X the width of the seed

How to Grow Helianthus:
Transplanting: Transplant when there are at least two sets of true leaves

Spacing: Plant out 2-4 feet apart in full sun in a light soil

Soil: Very tolerant of drought and poor soils

Temperature: Grow on at 70-75° days and 65-68° nights
Additional Care: If planted in partial shade, staking may be necessary to support plants, or plants can be pinched at planting to promote branching

Appearance and Use:

Grown for its edible seeds and for ornamental use in the border. These following flower in late summer and are very large and vigorous. Helianthus annuus, Common Sunflower, grows 4-6 feet tall with daisy-like flower heads in a multitude of sizes and colors, but generally with brown disk flowers and showy yellow ray florets. Helianthus debilis grows 4-7 feet tall and generally have 3 inch, yellow or white flowers. Helianthus giganteus, Giant Sunflower, is a perennial to Zone 3 but is commonly grown as an annual. It grows 9-12 feet tall and sports giant, 1 foot diameter flowers with light yellow to gold showy ray florets. All of the above have large, coarse, hairy, and somewhat sticky leaves


About Helianthus:
Pronunciation:  he-le-an’thus
Lifecycle:  Annual
Origination: Asteraceae, native to North America
Common Name: Sunflower