Digitalis ferruginea "Gelber Herold" (Yellow Harbinger) is a perennial foxglove from the Balkans.  Its tall spires of yellow-red flowers are veined in rusty red on the inside.  Growing to five feet tall, this perennial foxglove could easily be the focal point and star of the garden.  "Rusty Foxglove" has a long blooming period in sun or part shade and well-drained soil.  Zones 4-9.  Quarts.

Digitalis grandiflora/ambigua, a pale yellow perennial foxglove, pictured here amid Yellow Flag, Campanula persicifolia, and Sweet William, has always been my favorite of the perennial foxgloves.  It is neither as tall nor as showy as some of the biennial or perennial foxgloves, but it has a quiet, understated charm all its own that I very much admire.  Digitalis grandiflora is especially beautiful in my woodland garden where it can get a little shade.  The flowers are large, and the yellow is a pleasing, soft buttery yellow - not the jolting yellow associated with summer flowers.  It grows to about two feet in well-drained soil and partial shade.  Zones 3-8.  Quarts.

Digitalis lutea (Straw Foxglove) is a graceful perennial foxglove that is native to Europe and North Africa.  The three-foot spikes are smothered in small, pale yellow bells in summer and provide a long blooming period.  Not only that, but Digitalis lutea is long lived and likes to reseed.  What more could  you want in a perennial?  Sun/part shade.  Zones 4-9.  Quarts. (Photo by Bernd Haynold, Wiki Commons)

Digitalis obscura is different from other foxgloves I have encountered.  This one has willow-like leaves and, unlike its shade-loving relatives, it prefers sun.  It is a short-lived perennial, but it will self-seed, so keep that in mind when dead-heading.  Deadheading will prolong the blooming period, but be sure to stop at some point in order to have seeds.  This rusty-colored foxglove is heat and drought tolerant in Zones 5-9.  Quarts.  (Illustration from Curtis Botanical Magazine, John Sims, Wiki Commons).  Quarts.

Digitalis x mertonensis (Strawberry Foxglove) is quite showy: clump forming, deep green, fuzzy leaves and large, showy strawberry-pink tubular flowers.  Strawberry Foxglove is consdidered a biennial, but like other biennial foxgloves, it deserves a place in the garden.  Often, if the flowering stem is cut back after blooming, another plant will develop from the side, giving another plant and another year of blooms.  Also, after blooming, the clumps can often be divided and replanted.  Strawberry Foxglove grows in sun with some much appreciated shade to about three feet in moist, well-drained soil.  Zones 4-8.  Quarts.

Digitalis thapsi, a perennial foxglove that is native to Portugal and Spain, grows to about two and a half feet.  Its branched yellow stems hold large, nodding pink flowers that are white inside, and the flowers and foliage are dotted with yellow glandular hairs, lending a soft appearance.  Digitalis thapsi is similar to Digitalis purpurea in appearance, but it is somewhat shorter and often blooms the first year.  Give this perennial foxglove full sun/part shade in Zones 4-10.  Quarts.

Digitalis trojana, a striking biennial foxglove from Turkey, grows to about three feet. With bronze/yellow flowers, each with a white lip and a gold and rust-colored throat and silver/green leaves, it deserves closer inspection and a place in the garden. I read somewhere that it's hardly noticeable until it's in bloom, and its true. One day I had no notion of it, and then the next, there it was in full bloom. Be sure to let it reseed to keep it going on an perennial basis.  Sun/part shade. Zones 4-8. Quarts.   (Photo by Ghislain, Wiki Commons).