Maximilian Sunflower is a tall, erect, native perennial forb growing on branching hairy ridged stems from 5 to 7 feet high. The stem hair are short and fine giving a grayish-whitish color cast.

The leaves are all stem leaves, mostly alternate. The shape is lanceolate, 3x as long as wide, conduplicate, with 1 main nerve from a wedge-shaped leaf base which tapers to a very short stalk winged stalk. Leaf size decreases on the upper stem. Leaf margins are entire, the upper surface stiff and rough, the lower leaf surface will be rough from dense fine stiff hairs and is gland-dotted. The upper surface has a gray-green appearance due to the surface hair.

The floral array is a loose branched raceme-like cluster of 3 to 15 long-stalked hemispherical flower heads at the top of the stem with additional arrays branching from the upper leaf axils. Individual flower stalks are up to 4 inches long.

The flowers are composite, about 1-3/4 to 2 3/4 inches wide when open, consisting of an outer ring of 10 to 25 ray florets, which are not fertile; these have pale yellow rays, 25 - 40 mm long. The back surface of the ray floret laminae are not gland-dotted. These surround an inner disc of 75+ bisexual fertile tubular disc florets with deeper color yellow corollas that have five triangular throat lobes which spread when the floret opens. The five stamens of each disc floret have dark brown to black anthers which tightly surround a branched yellow style with an appendage that is usually yellow. Stamens and style are exserted from the tube when the floret opens. The flower head is hemispheric in shape surrounded with 30 to 40 green phyllaries, in several series, that are lanceolate in shape, loosely arranged or spreading, with pointed tapering tips. The margins of the phyllaries are usually finely hairy as is the outer surface, and gland-dotted.

Seed: Mature disc florets produce a dry cylindrical shaped brownish cypsela, 3 - 4 mm long, with a pair of awl-shaped awns on the top - no fluffy pappus. Seeds require 30 days of cold stratification for germination. If planted in the autumn, winter will do the work.

Habitat: Maximilian Sunflower grows from a rhizomatous root system that allow the plant to spread vegetatively and form colonies. Do not plant where you cannot control the spread. It needs full sun, and mesic to dry conditions. Various soils are tolerated, from sandy well drained to clays. Taller plants may need staking or the support of other plants. Powdery mildew and rust may affect the plants under certain conditions.

Names: The genus Helianthus is from two Greek words, helios for 'sun' and anthos for 'flower.' The species maximiliani is an honorary for Maximilian A. P. zu Wied-Neuwied (1732-1867), a German prince who traveled and collected in Brazil in 1815-17 and then in North America on his famous journey to the interior when he met the indigenous peoples and recorded aspects of the landscape, of which Karl Bodmer, who accompanied him, completed the famous set of North American Prints that Maximilian had published by Ackerman in 1840.

The author name for the plant classification, ‘Schrad.’ refers to Heinrich Adolf Schrader (1767-1836), German botanist, who taught at the University of Gottingen and wrote Nova genera plantarum and Flora germanica. The genus Schraderanthus is named for him. The description was published in 1834, the same year that Maximilian completed his North American work. It is not unreasonable to believe that Maximilian brought a specimen of this previously unclassified plant back to Germany with him for Schrader to use and this resulted in the honorary species name.

Comparisons: This species has similarities to H. giganteus (Giant Sunflower) which is also a tall plant, but with little stem branching. The fine grayish-white hair on stems and leaves, the long slim phyllaries and the one-nerved leaf which tends to fold at the nerve are good identification keys.