The common foxglove is a plant many of us are familiar with but do you know it's cousins?

Species

Digitalis cariensis

Digitalis ciliata

Digitalis davisiana

Digitalis dubia (syn. D. purpurea subsp. dubia)

Digitalis ferruginea - Rusty foxglove

Digitalis fontanesii

Digitalis grandiflora (syn. D. ambigua, D. macrantha, D. orientalis)

Digitalis laevigata
        Digitalis laevigata subsp. laevigata
        Digitalis laevigata subsp. graeca (syn. D. graeca)

Digitalis lamarckii

Digitalis lanata (syn. D. lamarckii (misapplied))
       Digitalis lanata subsp. lanata

Digitalis leucophaea (syn. D. lanata subsp. leucophaea)

Digitalis lutea - Yellow foxglove (syn. D. eriostachya)
       Digitalis lutea subsp. lutea
       Digitalis lutea subsp. australis (syn. D. micrantha)

Digitalis macedonica

Digitalis nervosa

Digitalis obscura - Willow-leaved foxglove
       Digitalis obscura subsp. obscura
       Digitalis obscura subsp. laciniata (syn. D. laciniata)

Digitalis parviflora (syn. D. kishinskyi)

Digitalis purpurea - Common foxglove (syn. D. minor)
        Digitalis purpurea f. albiflora (syn. D. purpurea 'Alba')
        Digitalis purpurea subsp. heywoodii (syn. D. heywoodii)
        Digitalis purpurea subsp. purpurea (syn. D. amandiana, D. miniana, D. nevadensis)
        Digitalis purpurea subsp. mariana (syn. D. mariana)
        Digitalis purpurea subsp. purpurea var. purpurea
        Digitalis purpurea subsp. purpurea var. tomentosa

Digitalis schischkinii

Digitalis sibirica

Digitalis stewartii

Digitalis thapsi - Mullein foxglove

Digitalis trojana

Digitalis viridiflora

Hybrids

Digitalis x fulva   Parentage: D. ferruginea  x D. grandiflora

Digitalis x fucata   Parentage: D. lutea x  D. purpurea

Digitalis x purpurescens

Digitalis x mertonensis   Parentage: D. grandiflora x D. purpurea

Groups & Series

Camelot Series (Camelot Cream, Camelot Lavender, Camelot Rose, Camelot White)
Excelsior Group
Glittering Prizes Group
Foxy Group (Foxy Apricot, Foxy Pink, Foxy Primrose)
Giant Spotted Group
Gloxinioides Group (Isabellina, The Shirley)


Cultivars

D. purpurea 'Suttons Apricot' (syn. D. purpurea 'Apricot Hybrids')

Boston Bells Parentage: seedling of  D. 'Genesis'

Butterfingers

Callisto Parentage:  D. 'John Innes Tetra' x  D. purpurea

Electrum Parentage: D. 'John Innes Tetra' x D. purpurea  f. albiflora

Elsie Kelsie

Foxley Primrose

Frosty

Genisis

Glory of Roundway Parentage: D. lutea x D. x mertonensis

Hildig(PBR)

John Innes Tetra   Parentage: D. grandiflora x D. lanata

Little Spook

Loxley Manor

Mary Burston

Mellenium Queen   Parentage: D. purpurea f. albiflora 'Anne Redetzky' (PBR) x D. purpurea

Mirabelle

Molten Ore

Nightshade   Parentage: D. davisiana x D. purpurea f. albiflora

Purple Dwarf

Red Skin

Silver Anniversary(PBR)

Spice Island

D. ferruginea 'Gleber Herold'

D. ferruginea 'Gigantea'

D. lutea 'Flashing Spires'

D. x fucata 'Aurora'

D. grandiflora 'Carillon'

D. grandiflora 'Dropmore Yellow'

D. grandiflora 'Dwarf Carillon'

D. grandiflora 'Dwarf Temple Bells'

D. grandiflora 'Temple Bells'

D. lanata 'Café Crème'

D. lutea 'Ray Holland'

D. lutea 'Sarah'

D. lutea 'Yellow Medley'

D. x mertonensis 'Raspberry'

D. x mertonensis 'Summer King'

D. parviflora 'Milk Chocolate'

D. purpurea f. albiflora 'Anne Redetzky' (PBR)

D. purpurea 'Berygold'

D. purpurea 'Campanulata'

D. purpurea 'Chedglow' (variegated)

D. purpurea subsp. heywoodii 'Silver Fox'

D. purpurea 'Pam's Choice'

D. purpurea 'Primrose Carousel'

D. purpurea 'Snow Thimble'

D. purpurea 'Tinkerbell'

D. purpurea 'Saltwood Summer'

D. thapsi 'Spanish Peaks'

D. trojana 'Helen of Troy'


This is by no means meant to be an up to the minute accurate list of Digitalis nomenclature, it's purely what I've been able to glean from various and usually reliable resources, however if you spot any potential errors or have an update please let us know.