Onopordum acanthium
(Cotton Thistle)

Family - Asteraceae
Category - Biennial
Origin - Europe to Central Asia
Season of Interest - Spring, Summer, Autumn
Hardiness - H5
Height - up to 3m
Width - up to 1m
Location - The White Garden

Description: A tall, rosette-forming Biennial with an upright, branching habit during. Large, hairy silver-green leaves with spiny-toothed margins are held in basal rosettes during the first year of growth and then Alternately arranged on the upright flowering stems during the second year. The upright stems have prominent, spiny-toothed wings. Many small, bright lilac-mauve, tubular flowers are held on a rounded, thistle-like flowerhead which is covered in silver webbing. The Blooms are held singly on the upright branching stems from midsummer into early autumn. Attractive to pollinating insects.

Gallery Images:

Flower:

Many small, vibrant lilac-mauve, tubular flowers are held in a nearly globular, thistle-like flowerhead (capitulum). The flowerheads are covered in web-like white hair and held singly on branched stems. The blooms are produced from July to September and are attractive to pollinating insects.

Flower colour: Purple

Flower shape: Tubular flowers held in a thistle-like capitulum

Flowering time: July, August, September

Foliage:

Large silver-green leaves are oblong to ovate in shape with pinnatifid lobing. The leaves are held in basal rosettes during the first year of growth. Tall, upright branching stems are produced during the second year of growth and have prominent, spiny-toothed wings. The leaves are Alternately arranged on the upright flowering stems.

Foliage Shape: Oblong to ovate with pinnatifid lobing

Propagation:

Seed.

Cultivation:

Best in full sun in fertile, well drained soil.