''Erysimum cheiri'',

syn. The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnae ...

''Cheiranthus cheiri'', the wallflower, is a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Brassicaceae (Cruciferae), native to Greece, but widespread as an

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived the ...

elsewhere. It is also treated as a hybrid under the name ''Erysimum'' × ''cheiri''. It is widely cultivated as a garden plant.

Name

The common name "wallflower" attaches to all cultivars of this plant, as well as other species within the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

''Erysimum'' and the former genus ''Cheiranthus''.

Description

This is a

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition ...

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

, often grown as a biennial, with one or more highly branching stems reaching heights of . The leaves are generally narrow and pointed and may be up to long. The upright to ascending shoot axes can lignify in the lower area. The lower leaves are in a rosette and have a short stalk. The leaf blade is up to 10 centimeters long, lanceolate and has double-stranded hair. The leaves along the stem axis are crowded, much smaller and almost sessile.

Inflorescence

The top of the stem is occupied by a club-shaped

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed ...

of 10 to 30 strongly scented, nectar-bearing flowers, the crown of which is yellow to brown or reddish in color due to the interaction of the red

anthocyanin Anthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical co ...

cyanidin with various

carotenoids Carotenoids (), also called tetraterpenoids, are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, ...

, and golden yellow in the wild form. Each flower has purplish-green

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

s and rounded petals which are two to three centimeters long and in shades of bright yellows to reds and purples. The flowers are quite large with a diameter of 20, rarely up to 25 millimeters. The scar is deeply bilobed, the lobes are later curved back. Pollination is carried out by bees and bumblebees. The flowers fall away to leave long fruits which are narrow, hairy

silique A silique or siliqua (plural ''siliques'' or ''siliquae'') is a type of fruit (seed capsule) having two fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit ...

s several centimeters in length. The upright pod is hairy, long, up to 3.5 millimeters wide and compressed from the back. The pods are wind spreaders.

Distribution

The wallflower is a garden refugee and originally native to south-east Europe, especially in the

Mediterranean basin In biogeography, the Mediterranean Basin (; also known as the Mediterranean Region or sometimes Mediterranea) is the region of lands around the Mediterranean Sea that have mostly a Mediterranean climate, with mild to cool, rainy winters and w ...

, where it grows in the wild in rock corridors. In

Central Europe Central Europe is an area of Europe between Western Europe and Eastern Europe, based on a common historical, social and cultural identity. The Thirty Years' War (1618–1648) between Catholicism and Protestantism significantly shaped the ...

, it is now a wild and naturalized archaeophyte, which occurs mainly in warmer areas, but is only scattered for the time being.

Cultivation

This is a popular

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

, widely cultivated for its abundant, fragrant flowers in spring. Many

cultivars A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...

have been developed, in shades of yellow, orange, red, maroon, purple, brown, white and cream. It associates well in bedding schemes with other spring flowers such as

tulip Tulips (''Tulipa'') are a genus of spring-blooming perennial herbaceous bulbiferous geophytes (having bulbs as storage organs). The flowers are usually large, showy and brightly coloured, generally red, pink, yellow, or white (usually in war ...

s and

forget-me-not ''Myosotis'' ( ) is a genus of flowering plants in the family Boraginaceae. The name comes from the Ancient Greek "mouse's ear", which the foliage is thought to resemble. In the northern hemisphere they are colloquially known as forget-me-not ...

s. It is usually grown as a biennial, sown one year to flower the next, and then discarded. This is partly because of its tendency to grow spindly and leggy during its second year, but more importantly its susceptibility to infections such as clubroot.

Cultivars

A miniature yellow double leafed wallflower was rediscovered by Rev. Henry Harpur-Crewe (before 1883) and is now named ‘Harpur Crewe’. Other bred varieties may vary in appearance from the wild plant. The following cultivars have gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (No ...

’s

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

:- *’Sunset Apricot’ (Sunset Series) *’Sunset Primrose’ (Sunset Series) Other varieties such as 'Blood Red Covent Garden' are easy to grow and often benefit from being sown and left to their own devices, growing on patches of empty land with little effort required to maintain them, providing aesthetically sound blooms which produce strong scents.

References

External links

Jepson Manual TreatmentUSDA Plants ProfilePhoto gallery
{{Taxonbar, from=Q159370 cheiri Flora of Europe Garden plants of Europe Plants described in 1753 Taxa named by Carl Linnaeus