South Dakota Native Plant Research
 
Asteraceae : Helianthus annuus

Asteraceae : Helianthus annuus

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Family Name

Asteraceae

Common Name

Common sunflower

Native American Name

Lakota: waȟčá zizí, waȟčá zí tȟáŋka

Description

Helianthus annuus is an annual, erect, coarse, tap-rooted plant with stems that are 0.6-3 m tall and rough-hairy. The lower-most leaves are opposite, but most of the leaves are alternate with a long petiole. The blades are ovate to triangular, 10-40 cm long and 5-20 cm wide, egg-shaped to triangular, with toothed to almost entire margins and 3 primary veins radiating from the base. There are 1- many heads in the inflorescence, with each flower head attached to a long peduncle at the end of a branch, the heads are 7.5-15 cm wide, and the involucre has several series of ovate bracts with a long abruptly tapered tip, that often have short hairs along their edges. The 10-40 ray flowers are yellow, the ligule 2.5+ cm long. The numerous disk flowers are reddish-brown to purple or rarely yellow. The achenes are 3-15 mm long. Common sunflowers bloom from July through September in open sites and disturbed areas throughout South Dakota.

Additional Notes

Sunflowers are an easy to grow plant and will adapt to almost any native plant garden. They were in cultivation long before Europeans came to North America. Over the last 3,000 years the indigenous peoples of this continent increased the seed size approximately 1,000 percent. Sunflower seeds were and still are eaten raw, roasted, cooked, dried, and ground, and used as a source of oil.

Horticulture Notes

Seed Collection: Collect seed in Aug.-Sept.
Germination: No pretreatment needed.
Soils: Moderately rich and well-drained.
Light: Full sun to partial shade
Water: Dry to moist.

Asteraceae : Helianthus annuus

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