Digitalis ferruginea aka Rusty Foxglove

Digitalis ferruginea is also called rusty foxglove. It belongs to the Plantaginaceae family. Its native range runs from Hungary to the Caucasus and Lebanon. It grows in parts of Europe and western Asia with temperate climates. Wild plants grow in woods and grassy clearings. They also grow in scrub and on rocky slopes. These sites reach about 8,860 feet [2,700 metres] above sea level. It is not native to Britain or Ireland.

This upright plant is a perennial, living for several years. Gardeners often grow it as a biennial, over two years. Dark green leaves have a lance shape. They form a rosette, or ring, at ground level. Some leaves stay through winter, making the plant semi-evergreen. Tall flower stems rise above this low base. Garden plants reach 3.3–4.9 feet [1–1.5 metres] tall. Their spread ranges from 0.3–1.6 feet [0.1–0.5 metres]. The RHS gives two to five years to reach full size.

Tall racemes, or flower clusters, carry blooms shaped like tubes. Each bloom opens like a bell. Each flower measures about 1.4 inches [3.5 centimetres] long. The blooms range from cream-yellow to pale golden brown. Rust-coloured veins mark the inside of each bloom. Missouri Botanical Garden lists May to June for bloom time. Chicago Botanic Garden gives the same months. The RHS gives the broader season of summer. The flowers draw hummingbirds and suit use as cut flowers. Their tall stems add height to beds and borders. Dark walls or shrubs make a useful backdrop. The plant also suits woodland gardens and areas with natural planting.

It prefers soil rich in humus and a partly shaded site. The RHS says it also tolerates sun or full shade. It accepts chalk, clay, loam, and sand across the pH range. Keep the soil moist, but let excess water drain. Avoid sites that stay very wet or become very dry. It needs moderate watering and little care. Listed hardiness is USDA zones 4–8 and RHS H6. Sow seed in a cold frame during late spring. Divide plants in early spring. Remove the main flower spikes as they fade. This helps side shoots grow and bear flowers.

Reports of serious pest and disease problems are not common. Still, mildew and leaf spot can harm leaves by midsummer. Aphids, mealybugs, and slugs may attack plants. Japanese beetles and eelworms may attack them too. Crowns can rot in wet winter soil. Deer tend to avoid the plants. All parts are poisonous and pose risks to people and pets. There are no known edible uses. Sources record use of the leaves to treat heart complaints. This does not make the plant safe to eat. Wear gloves and protective clothing when you handle it.