Vernonia crinita Mammuth - Ironweed

Vernonia crinita 'Mammuth' is a very tall perennial related to asters and resembling eupatoriums. It forms a large clump adorned in late summer with numerous compound, violet mauve and slightly crumpled flowers. Withstanding harsh winters and scorching summers without weakening, it will grow in all types of soil as long as they are not too dry. Still relatively uncommon in Europe, this sturdy American plant explodes in a fireworks display when in bloom. It will fit well in informal, somewhat wild gardens, where its robustness makes a difference. It is an ideal plant to bring height to the back of a border, or near water features.

Vernonia crinita 'Mammuth' belongs to the asteraceae family. It is a herbaceous perennial with a woody base that reaches 1.70 m (6ft) high and spreads 50 cm (20in) across. Its growth is quite rapid, but it takes two years to establish. It forms a clump of large and robust, straight and sparsely branched stems, bearing alternate, simple, lance-shaped, dark green leaves. From July-August to September-October, it has violet-mauve flowers, resembling fluffy little pompoms, which turn rusty as they age, in broader terminal corymbs than the species, at the end of the stems. The long-lasting flowers all open at the same time and attract a large number of butterflies, creating a magnificent spectacle.

This highly hardy vernonia is easy to grow and pairs well with a multitude of plants to create magnificent autumn compositions, especially on the banks of a pond. Plant it alongside similar-looking eupatoriums, Lythrum salicaria, Filipendula rubra 'Venusta', and Euphorbia palustris, for example. In a wilder style, at the back of a border, this imposing perennial forms a very successful combination with tall grasses: Miscanthus, Panicum, Stipa...