Common Name: rusty foxglove
Type: Herbaceous perennial
Family: Plantaginaceae
Native Range: Europe
Zone: 4 to 8
Height: 3.00 to 5.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: May to June
Bloom Description: Creamy yellow to pale golden brown with rusty interior veining
Sun: Part shade
Water: Medium
Maintenance: Low
Suggested Use: Naturalize
Flower: Showy, Good Cut
Attracts: Hummingbirds
Tolerate: Deer
Culture
Easily grown in average, medium, well-drained soil in part shade. Prefers moist, organically rich, acidic soils. Soil must not be allowed to dry out. A biennial or short-lived perennial which may be grown from seed sown directly in the garden in spring after threat of frost has passed for flowering the following year. Only a basal rosette of leaves is produced in the first year from seed. This rosette overwinters as evergreen foliage, with slender flower spikes rising from the rosette in the following spring for bloom in late spring to early summer. Removal of flower spikes after bloom will encourage a secondary bloom. Cut all flowering stalks back to basal foliage before seed sets in order to encourage plants to act as perennials. If flower spikes are left in place after flowering and allowed to go to seed, plants will act more as biennials and will, in optimum growing conditions, freely self-seed. However the spent flower spikes can rapidly become quite unsightly as the seed develops and many gardeners choose to remove most spikes and leave only a few for self-seeding. As with other biennials/short-lived perennials such as hollyhocks, these plants can remain in the garden for many years through self-seeding as if they were long-lived perennials, often establishing large colonies in optimum growing conditions.
Noteworthy Characteristics
Digitalis ferruginea, commonly called rusty foxglove, is a biennial foxglove that produces only a basal rosette of medium green, oblong leaves in the first year from seed. Flowers are borne in the second year in terminal racemes (2-3' long) atop leafy, 3-5' (infrequently to 6') tall spires arising from the centers of the basal rosettes. Pendulous to horizontally-held, 0.75 to 1.5" long, tubular, funnel-shaped, creamy yellow to pale golden brown flowers with rusty interior veining and longer than usual lower lips are closely grouped along each spike. Plant leaves are a source of the drug digitalis and are highly poisonous. A late spring to early summer bloomer. Individual flowers resemble the snipped off fingers of a glove, hence the common name of foxglove.
Genus name comes from the Latin digitus meaning "finger" for the flower shape.
Specific epithet means rusty colored.
Problems
No serious insect or disease problems. Powdery mildew and leaf spot, if left untreated, can depreciate foliage considerably by mid summer. Dense crowns may rot in soggy, poorly-drained winter soils. Potential insect pests include aphids, mealy bugs, slugs and Japanese beetle.
Uses
Tall spires provide striking color and good architectural height to the border and are particularly effective in front of dark backgrounds such as those provided by a wall or shrubs. Also effective in woodland gardens or naturalized areas.