Easily confused with : Garden
Phlox flowers, but they do not have notched petals nor are they zygomorphic with bilateral symmetry like Fairy Foxglove is, but rather are actinomorphic with radial symmetry. Fairy Foxglove is slightly zygomorphic, hence hemi-zygomorphic. Sometimes the flowers are partially or wholly inverted. A number of differing cultivars exist, the above are probably cultivars rather than truly wild since they were mostly growing on garden walls.
No relation to : Fairy Flax (a plant of very similar name) which is in the Flax family), nor to Fairy Fern.
Not to be confused with:
Phlox. Flax and Phlox are quite different flowers that happen to look very similar; Phlox being a low-growing garden ground-cover plant with the same five petals (usually notched similarly), and being similarly coloured (but without the yellow centre.
Not much relation to : Foxglove (a plant of very similar name, and which also happens to be in the same Plantain family). The flowers of Foxglove are weakly two-lipped; those of Fairy Foxglove not so.
More likely to be found in a rock garden or the wall of a garden than growing wild.
The only flower in the Genus Erinus (or at least in the UK).