Heleniums are members of the Aster family (Asteraceae). The species from which the garden forms of Helenium are derived grow in the wild in North America. The genus contains about 40 species of annuals and perennials although the Index Kewensis lists names when subspecies and synonyms are taken into account. There are only a few which have been used in developing cultivars for the garden. Here we attempt to give an outline of the most important species. This can help in understanding the best conditions for their garden cultivation.
Approximate wild distribution of 4 important Helenium species Yellow - Helenium autumnale, Orange - H autumnale + H flexuosum, Green - H bigelovii, Blue - H hoopesii.
This is the most widely distributed species. Helenium autumnale is found in wet meadows, thickets, and even swamps and river margins. In the wild it is reported as growing from 50cm to 150cm tall with smallish yellow single daisy flowers of heads of 25 to 40mm across from August to November. This species is found from New England across the mid west and into the Rockies. It grows in hardiness Zones: 3 to 8 and is found in 34 states of the US and several Canadian provinces including Alberta, Quebec and Ontario. There is conflicting information about the presence of the species in northwestern states. Helenium autumnale is reported as able to withstand temperatures down to -40 C. Clearly with such a wide distribution it is important to obtain seed for sources of sufficient hardiness for one's growing conditions.
Helenium autumnale form JLS8807W1 collected from the wild showing typically "gappy" petals and prominent yellow cone (disk).
The plant is a perennial herb and grows from a crown of resting shoots. Leaves are alternate, simple, elliptic to lanceolate, serrate to almost entire, 6 to 15 cm long, 1 to 3 cm wide. The bases of the leaves continue as ridges down the stem. Not usually eaten by livestock, it is reported to contain a toxic glucoside known as dugaldin. The common name is believed to be derived from the former use of the dried leaves to make a snuff. This was inhaled by native Americans to promote sneezing and rid the body of evil spirits.
Purple-headed sneezeweed was originally a southern species but is migrating northwards. It is much shorter than the previous species - height 40 -70 cm and has a dark brown cone (or disk) sometimes with a purple hue.
Helenium flexuosum in the wild © George F. Russell and courtesy of USDA Natural Resources Conservation Service
Helenium flexuosum flowers from June to October. It is found in damp meadows, thickets, and waste ground. Some garden cultivars such as Helenium Wesergold share many of the characteristics of this species.
Helenium flexuosum © Michael Thompson & taken in the wild in Kentucky, USA.
Bigelow's Sneezeweed. Found in moist or wet habitats associated with Yellow Pine Forest, Red Fir Forest, Lodgepole Forest, and Subalpine Forest in western N America from 1000 to 3000 metres. At least one garden form (Helenium 'The Bishop') is closely related to this species.
Helenium bigelovii in the wild © Charles Webber, California Academy of Sciences.
Other species of interest
synonyms: Dugaldia hoopesii & Hymenoxys hoopesii. Common names: Owl's-claws, Hoope's sneezeweed. Grows from a woody taproot, reproducing only by seeds - unlike other Heleniums which can be divided successfuly in early spring. Young plants covered with very fine soft hairs but become nearly hairless as they age. Flower heads are 30 to 70mm across. Flowers June to September on moist but well-drained mountain meadows, also the deep rich soils of coniferous forests.
Coastal Sneezeweed. Found only in the coastal scrub of the NW counties of California and usually in wet areas. Grows at low altitude.
Photo © Charles Webber, California Academy of Sciences.
Sneezeweed or Rosilla. Occurs in moist conditions in meadow habitats between 0 and 600 metres throughout California. California Academy of Sciences website contains more photos.
Photo © Br. Alfred Brousseau, Saint Mary's College.