Gard. Dict. ed. 8, Digitalis no. 4 [. as magno flore], corr. 1768
Stems 50–100 cm, pilose to villous, hairs glandular and eglandular. Leaves: blade lanceolate to oblanceolate, 10–21 × 2–4 cm, margins finely and evenly serrate distally, with a glandular tip. Inflorescences secund, glandular-pilose, bracts 20–30 mm. Pedicels pendent, 5–12 mm, glandular-pilose. Flowers: sepals narrowly lanceolate, 8–12 × 1.5–2 mm, villous; corolla tube pale yellow, funnelform, 25–40 mm, throat 14–20 mm diam., abaxial lip pendent, pale yellow often marked by brown veins, broadly rounded to broadly triangular, 3–4 mm. Capsules ovoid, 8–11 mm, glandular-pilose. Seeds brown to black, prismatic, 1 mm, finely reticulate-alveolate. 2n = 56 (Europe).
Phenology: Flowering Mar–Jul.
Habitat: Disturbed sites, roadsides, old fields.
Elevation: 0–1000 m.
Introduced; Ont., Conn., Maine, Mass., Mich., Minn., Mont., N.H., N.Y., Ohio, Vt., Wis., e Europe, w Asia, introduced also in South America, elsewhere in Europe, elsewhere in Asia, Africa, Australia.
Plants of Digitalis grandiflora are occasionally found in cultivation and sometimes escape in the northeastern part of the flora area.
Although the names Digitalis grandiflora and D. orientalis were published at the same time, D. grandiflora has long been the preferred name for this species and has been in general use since it was published. The name D. orientalis Miller was long confused with the later homonym D. orientalis Lamarck, a synonym of D. lanata.