Erysimum make up a large genus of plants that can be hardy annual, hardy biennial, or hardy perennials in nature. They can range from 15 cm to about a metre (6 to 40 inches) in size.
They are very similar to Cheiranthus true wallflowers, hence some of their common names.
Some names for Erysimum include Alpine Wallflower, Coastal Wallflower, Siberian Wallflower, and Blister cress.
Erysimum capitatum - Western Wallflower by Miguel Vieira
They have foliage that is lance like. Plants bloom in the spring, with yellow, purple, or orange four petaled flowers.
Depending on the species, they can be used in both rock gardens or in the border.
Some of the latin names of these plants include Erysimum cheiri, Erysimum cheiranthoides, Erysimum linifolium, and Erysimum allionii.
Erysimum asperum - Prairie Rocket Wallflower by Photogramma1.
Erysimum capitatum (Sanddune wallflower / Western wallflower / Prairie rocket), photograph by Matt Lavin; CC.
Erysimum cheiri (Wallflower), picture by Dr Mary Gillham Archive Project; CC.
Erysimum repandum (Spreading wallflower / Spreading treacle mustard / Bushy wallflower), Image by Radu Chibzii; CC.
Erysimum linifolium (Alpine wall flower), photograph by Forest and Kim Starr; CC.
Erysimum 'Bowles Mauve' Cultivar photograph by Leonora (Ellie) Enking; CC.
Erysimum 'Winter Joy' Cultivar photograph by Valleybrook Gardens; CC.
Erysimum 'Winter orchid' Cultivar photograph by Valleybrook Gardens; CC.
Common Names: Wallflower, Blister Cress. Wallflower: Siberian; Alpine; Western; Diffuse; Wormseed; Smelly; Pallas'; Kotschy; Coastal; Shy; Fairy; San Francisco.
Life Cycle: Hardy annual. Hardy biennial. Hardy perennial.
Height: 4 to 50 inches (10 to 130 cm).
Garden Location: Rock gardens, Beds, Borders, by Walls, Containers. Many species thrive in sandy coastal areas.
rock gardens or in the border Native: Mediterranean, North and Central America, Europe, Southwestern Asia.
It depends on the species as to when the Erysimum seeds should be planted out:
1. Annuals: Sow seeds in Autumn or spring.
2. Biennials: Start in spring, move in autumn.
3. Perennials Spring or Autumn
Seeds should be planted at a depth of about 7 mm (1/4 inch) into a sunny part of the garden that has good drainage.
They usually take about two to four weeks to germinate. Wallflowers and other Erysimum members like a dry soil of pH 5 to 8.
Once growing you should care for Erysimum wallflowers by deadheading after flowering. Provide them with a mulching in the Autumn.
If you require more plants then cuttings should be took in the spring; as Erysimum plants self seed this may not be necessary.
I hope that you enjoyed this guide on how to grow Erysimum plants. You may also enjoy the following Gardener's HQ Brassicaceae growing guides: How to grow Sea kale, Thuja occidentalis, Parsnip and Iberis plants.