Parthenium integrifolium

Parthenium integrifolium, locally known as Wild Quinine or Great American Chamomile, is a perennial and medicinal plant that grows and flowers without care in the great plains of the eastern and Midwestern United States. It forms a large leafy clump and blooms throughout the summer in aerial inflorescences composed of a multitude of small globular and woolly, almost white flowers, reminiscent of those of Statice or Immortelles. Withstanding both cold and heat, it adapts well to any well-drained soil, even somewhat dry in summer. Interesting for bringing lightness and transparency to a massif, this perennial is perfect in a wild garden.

Parthenium integrifolium belongs to the Asteraceae family, just like chamomiles and daisies. It is a native botanical species in the states of Texas and Oklahoma, north of Minnesota, and east of Massachusetts. It is found in meadows, forest edges, slopes, and disturbed areas, often on clay-loam or sandy loam soils. It is a herbaceous perennial plant with its growth emerging from the ground in spring and drying up in autumn. An adult specimen forms an upright clump about 80cm (32in) tall and 50-60cm (20-24in) wide. The stems bear glandular leaves of varying sizes and oval to lanceolate shapes, with toothed, dentate, or lobed margins. Their colour is a beautiful bright green. The flowering period extends from June to September. The inflorescence, which stands above the vegetation, is a cluster of several heads, each containing at least 15 florets. Each floret consists of a central whitish cottony disc surrounded by 5 to 6 papery-textured florets. The flowers have a pleasant, soft, slightly medicinal scent. This flowering is highly visited by bees. The faded inflorescences remain decorative for a long time, until winter. They can be advantageously used in dried flower arrangements. This plant was used for medicinal and veterinary purposes by Native Americans.

Wild Quinine is a lovely unpretentious plant for a garden that leaves room for nature. Its flowering remains decorative for a long time and it brings lightness to flower or shrub borders. Its excellent hardiness (-25°C (-13°F)) and heat tolerance allow it to be adopted in many regions. For example, it can be associated with roses, as it plays a similar decorative role as paniculate Gypsophila while being much less fragile. Its combination with perennial sages (Salvia pratensis 'Evelyne') or shrub sages is also very successful. In a naturalistic setting, consider planting this Parthenium with grasses and Echinaceas, Lychnis coronaria, thistles...