Erysimum cheiri, Cheiranthus cheiri 'Fire King'

Erysimum cheiri, formerly Cheiranthus cheiri ‘Fire King' is another old and tried variety, with striking, flame-like, glowing orange-scarlet flowers. A compact variety with a bushy habit which is a perfect foil for daffodils and many other spring bulbs. Extremely easy to grow and very rewarding, no flower is more delightful in early spring.

This English cottage plant gives fragrant clusters of blooms from mid-spring and throughout summer. They are especially valuable because they bloom in the period between primroses and summer annuals. Ideal for borders and edging, they could also be used in large containers.
With a rich fragrance that is most pronounced on a sunny day, they will supply the household with an abundance of cut flowers for many weeks.

Wallflowers, which along with similarly fragrant Stocks, are called giroflées in French (literally, 'clove-scented'), are widely grown as winter bedding plants and are found self-sown through many cottage gardens and their walls. That's where they get their English name of 'wallflower': they love the sharp drainage of a little pocket of gritty soil in a stone wall.
That's a hint on how to grow wallflowers: give them excellent drainage, especially if you have clay soil. Mix some coarse sand and compost into the planting area. And give them full sun; wallflowers aren't meant for shade.

Wallflowers prefer temperatures of 21°C (70°F) days and 10°C (50°F) nights and can flower in moderate heat at a maximum temperature of 27°C (80°F). Plants require 70 to 80 days to flower from sowing and will start flowering when they are 10cm (4in) tall. Start in pots or sow direct in late summer, Mid August through to mid September.

Sowing:
Sow in late summer to early winter (June to Aug) for spring flowering or sow in late winter to early spring (Jan to Mar) for autumn flowering.

Starting in Pots:
Surface sow in pots or containers containing good quality seed compost (John Innes or similar) Cover with a fine thin layer of compost or vermiculite.
The compost should be kept moist but not wet at all times. Seed germinate in seven to 10 days at 20°C (68°F).
Prick out each seedling as it becomes large enough to handle, transplant into 7.5cm (3in) pots. Gradually acclimatise to outdoor conditions for 10 to 15 days before planting out after all risk of frost.

Sowing Direct:
Seeds may also be sown outdoors directly where they are to flower or in a reserve bed in a sheltered position. Prick out to 15cm (6in) apart and transplant in October.

Cultivation:
Deadheading wallflowers prolongs their bloom, but let some of them go to seed. They are often generous self-sowers, or you can gather the seed and resow it yourself.
All parts of the plant are poisonous. specially the seeds. Plant contains Cheirotoxin that has similar but lesser toxic effects as Digitalis does.

Plant Uses: Plant in rock gardens, containers, beds, and borders.
Wallflowers are pleasant by paths and doorsteps, and will bloom all winter in a cool room in sunlight. They make good cut flowers, too.
They look great interplanted with tulips, especially the lily-flowered types whose elegant forms contrast nicely with the mounded flower heads of the wallflowers.

Origin:
There are basically two types of wall flower, ‘Siberian’ and ‘English’. The Siberian types have flowers that are always orange or yellow-orange, with the English types having purples, whites and pinks as in the picture above. Both make good garden plants
A member of the Brassicaceae family, isn't it interesting that the cabbage family gives us some of our most fragrant florals, including not only wallflowers, but also garden stocks and the wonderful night-scented stock! While the vegetable branch of the family is rather smelly and malodorous, due to the high sulphur content of their leaves, the members grown for their flowers couldn't smell more bewitching. One of the innumerable mysteries of the garden... !

Nomenclature:
Wallflowers have a long history. The heavily scented biennial flower was commonly carried as a nosegay to smother the stench of Elizabethan streets. And the name cheiranthus is thought to derive from the Greek for hand (cheir) and flower (anthos), indicating their use as a floral version of the pomander.

John Gerard, writing in 1596, said that "the wallflower groweth on bricke and stone walls, in the corners of churches, as also among rubbish and other such stony places everywhere", alluding to how the plant got its common name, as well as its love of good drainage and sun. Many varieties have been around for at least a century and some bear the prefix Bedder, an indication of their wide use in Victorian planting schemes.