Chiba University Matsudo/Kashiwa Campus Plant Database

Details of genus: Helianthus L. [817]

genus_ja:

genus_en: Sun flower

# spp.:

pub_year:

accepted: Accepted

Family: Asteraceae

family_ja: キク

Infra familial classification:

distribution_en:

description_en: Genus of about 70-80 species of annuals and perennials, some occurring in dry woodland and prairies, others in damp, swampy habitats, in North America, Central America, Peru, and Chile. Usually tall, coarse plants, they have creeping or tuberous roots and large, simple, bristly, alternate or opposite leaves. The showy, daisy-like flowerheads, with sterile ray-florets, are usually 5-10cm (2-4in) across, but up to 30cm (12in) in the giant annuals; they are borne singly or in loose corymbs and have yellow, occasionally red, or very rarely violet, ray-florets, and yellow, brown, or purple disc-florets. As the nomenclature of many cultivars and hybrids is confused, some names used here may be amended in the future. Sunflowers are effective in an annual, herbaceous, or mixed border. The taller, spreading species and hybrids, such as H. x laetiflorus and H salicifolius, are suitable for a wild garden; small annuals, such as H. annuus ’Teddy Bear’, are ideal for containers. Sunflowers provide good cut flowers and many are attractive to bees. Contact with the foliage of sunflowers may aggravate skin allergies.

hardiness_en: Fully hardy to frost hardy.

cultivation_en:

propagation_en: Sow seed of perennials in containers in a cold frame in spring; sow annuals at 16°C (61°F) in late winter, or in situ in spring. Cultivars may not come true from seed, and hybridize freely. Divide perennials in spring or autumn. Root basal cuttings in spring.

pests_en: Susceptible to slugs, powdery mildew, and Sclerotinia.

description_ja:

comment: America

comment_ja: ヒマワリ，キクイモ

type_species:

Phylogenetic definition:

Update Information: Created: 2007-12-06 12:51; Updated: 2020-09-04 03:56

family: