The genus digitalis consists of about twenty species, and numerous hybrids, of biennial plants originating in Europe, now widespread in America, Africa and Asia. In the first year of life the digitalis purpurea plant does not produce flowers, it consists only of a basal rosette of long dark green lanceolate leaves, sometimes covered by a whitish woolly down.
In the second year of life from the center of the rosette, in June, a long stem grows, covered by only one side with large tubular flowers, of decreasing dimensions from the base to the apex of the stem, of various color, from white to pink to violet, up to the yellow and cream of some hybrids, often spotted with a contrasting color on the inside.
The digitalis plant flowering lasts about a month, but if the ear is cut off once it has faded, it is likely that in late summer the plant will produce another one.
The plants belonging to the variety digitalis purpurea they grow without problems in any position, both in full sun and in the complete shade; in areas with very hot and dry summers it is advisable to cultivate them in the shade, to prevent excessive heat from ruining the plant. Usually digitalis are grown in the shade but they do better when the brightness is still noticeable and the temperature is pleasant.
If the winters are particularly harsh it is advisable to cover the rosette of leaves with mulch in autumn to protect the specimens from cold temperatures.