Published by Brian Wagner on 10/13/25 in “Growing Flowers from Seed.”
Erysimum cheiri (commonly called fragrant wallflower) belongs in cottage gardens. It is a short-lived, base-woody perennial often grown as a biennial. In the United Kingdom, the classic spring ‘bedding wallflowers’ are various cultivars of this species.
Native to Europe, E. cheiri thrive naturally on sun-exposed, dry, nutrient-lean calcareous sites – often on rocky slopes and shrub-dominated banks. These are conditions not too dissimilar from Mediterranean scrublands (or the desert-like area surrounding Los Angeles). They are also observed growing among grassland habitats, albeit to a lesser extent.
As a member of the Brassicaceae family, they have the classic four-petal, cross-shaped flower head. You’ll find similar flower heads among Broccoli or Kale flowers before going to seed.
Growing From Seed
Like most Brassicaceae plant seeds, Erysimum cheiri are suspected to have a non-deep physiological dormancy (PD). It is very common for seeds with a non-deep PD to exhibit a behaviour called after-ripening where their dormancy dissipates with the passage of time – and faster if seeds are held at room temperature (i.e., compared to colder temps). It is thought that the seeds experience free radical damage but are unable to repair themselves in the dried state.
However, if sowing fresh seeds you would need to cold stratify them for 6 weeks at 4C (40F) prior to sowing them on the surface; they will prefer light to germinate. Keep temperatures around 15C (60F) if you can, and do not use a heat mat. (Almost never use a heat mat for non-deep PD seeds.) They should germinate within a week.
The seed gardener can also simply wait. Seeds should after-ripen after 3-6 months of dry storage at room temperature, in which case they should not require cold stratification and can simply be sown at 15C (60F) with light.