Digitalis

( dij - ee - TAH - liss )

At-A-Glance Information

This genus of perennials and biennials commonly called Foxgloves need regular water, and their sunlight needs vary depending on the species. Large flowers will attract birds and butterflies to your garden. They are mainly from the Mediterranean and Europe, and reach 2-8 feet tall at maturity, forming clumps of gray-green foliage. Flower color can be purple, yellow, white, or various pastel colors. These statement-making beauties are great for many garden uses, including as color in beds, for cut flower gardens, along pathways and roadsides, in rock gardens, and at woodland edges. Take care when planting these beauties in your garden, however, as all parts are poisonous if they are ingested.

Digitalis Species and Varietals

The genus Digitalis includes around 20 species and is a member of the plant family Plantaginaceae. Foxglove growing zones vary depending on the individual species requirements. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Digitalis canariensis (Isoplexis canariensis) (Canary Island Foxglove, Crestgallo)
Reaching about 5 feet tall at maturity, this evergreen species of Foxglove is native to the Canary Islands, and forms a rounded shrub. Large inflorescences of orange-reddish flowers bloom in spring and summertime. This species grows well in USDA hardiness zones 9a-11b or Sunset growing zones 14-24.

Digitalis ciliata (Hairy Foxglove)
Native to the Caucasus, this species of Foxglove produces light cream-yellow flowers and has evergreen foliage. Stems and flowers are hairy, hence the common name Hairy Foxglove. Individual plants reach between 12 and 20 inches tall at maturity. Hairy Foxglove grows well in USDA hardiness zones 4-9.

Digitalis davisiana (Davis' Foxglove, Alanya Foxglove)
This species of Foxglove is native to Turkey and is named for British botanist Peter Hadland Davis, who was very active in describing the flora of the country. The species grows well in USDA hardiness zones 5a-9b. These perennial plants flower in early summertime and reach 28 inches tall and 12 inches wide at maturity when in bloom. Leaves are green and flowers are pale yellow with orange veining.

Digitalis ferruginea (Rusty Foxglove)
This is a short-lived perennial, treated commonly as a biennial. It grows best in USDA hardiness zones 4-9 or Sunset growing zones 1-10 and 14-24, and reaches up to 4 feet tall and 1.5 feet wide at maturity. They need full sun or light shade and produce yellow flowers with rusty-red markings. Varieties include 'Gelber Herold' and 'Gigantea'.

Digitalis grandiflora (Yellow Foxglove, Big-Flowered Foxglove, Large Yellow Foxglove)
Native to Europe and Asia, this species produces flower stems that reach between 28 and 47 inches tall. Blooms are pale yellow and bell-shaped, flowering in June and July in their native habitat. Typical bloom period is about 8 weeks long. This species is considered a long-lived perennial, and has a few notable cultivars, including 'Carillon' and 'Temple Bells'. Best in USDA zones 3-8.

Digitalis spp. Hybrids (Hybrid Digitalis, Hybrid Foxglove)
This group of hybrids were created by crossing various species in the genus, and were bred for large flower spikes and unique bloom colors. These flowers grow well in USDA hardiness zones 4-9. Cultivars are listed below:

'Alba'

'Arctic Fox Rose'

'Apricot Beauty'

'Camelot Lavender'

'Candy Mountain'

'Dalmatian Peach'

'Dalmatian Purple'

'Gelber Herold'

'Illumination Flame'

'Pam's Choice'

'Pantaloons'

'Polkadot Polly'

'Polkadot Princess'

'Rose Ivory'

'Ruby Glow'

'Serendipity'

'Sugar Plum'

'Sutton's Apricot'

Digitalis laevigata (Grecian Foxglove, Giraffe Foxglove, Smooth Giraffe Foxglove)
This species grows best in USDA hardiness zones 4a-8b or Sunset growing zones 3b-10 and 14-24 and is a perennial that gets to 3 feet tall and half as wide. Dark green leaves are smooth and flowers are a creamy yellow with purple-brown freckles. Takes full sun but can tolerate light shade conditions. These plants bloom from May through July in their native range.

Digitalis lamarckii (Lamarck's Foxglove)
This interesting species of Foxglove is native to Turkey, and produces brownish to greyish-green foliage. Flowers are cream to white with brown/maroon veining and a prominent protruding white lower lip. Lamarck's Foxglove does well in USDA hardiness zones 3-9.

Digitalis lanata (Wooly Foxglove, Grecian Foxglove)
This species is a biennial or short-lived perennial that grows best in USDA hardiness zones 4-9 or Sunset growing zones 2b-10 and 14-24. Gets to 2 feet tall and 1 foot wide with creamy tan flowers marked with brown. Needs full sun or part shade for best performance. This species is considered invasive in the United States (Minnesota, Wisconsin, Kansas).

Digitalis lutea (Straw Foxglove, Small Yellow Foxglove)
This species grows best in USDA hardiness zones 3-9 or Sunset growing zones 1-10 and 14-24 and is a Mediterranean native perennial plant. Gets 2.5 feet tall and 15 inches wide with spires of pale yellow flowers with brown freckles. Varietal 'Flashing Spires' has yellow variegated leaves. They need partial to full shade but can take full sun in cool-summer climates.

Digitalis mariana (Digitalis purpurea subsp. mariana)(Foxglove, Silver Fox)
Native to Portugal and Spain, this species of Foxglove does well in mountainous areas, where they grow amongst rocks in acidic soil. Foliage is evergreen and light grey-green, and flowers are rosey-red to pink, blooming in summertime. This species does well in USDA zones 5-9.

Digitalis minor (Dwarf Spanish Foxglove, Didalera, Didalis, Didals de la Mare de Déu, Boca de Llop, Herba de Santa Maria)
This low-growing species is native to Balearic Islands of Spain, and grow to reach about 30 inches tall. These plants are considered biennials or short-lived perennials. Flowers are light pink with cream colored throats dotted with dark pink markings, and bloom from May through June in the plant's native range. Best in USDA zones 8-10.

Digitalis x mertonensis (Strawberry Foxglove)
This hybrid perennial species of Foxglove reaches up to 2-3 feet tall and 1 foot wide at maturity. Blooms are rose colored, and appear in spring or summertime. These plants can take full sun in cool-summer climates, but usually need partial to full shade, growing well in USDA hardiness zones 4-9.

Digitalis nervosa (Tall Armenian Foxglove)
This species is native to Iran up through the Caucasus, and form a woody rootstock. Flowers are rusty yellow and bell shaped, marked with red to maroon markings in the throat. These plants flower from July through August in their native range. Hardy down to -4 degrees Fahrenheit. Best in USDA zones 4-8.

Digitalis obscura (Narrow-Leaf Foxglove, Dusty Foxglove, Spanish Rusty Foxglove, Willow-Leaved Foxglove)
This species of Foxglove is woody and a perennial, and grows in USDA hardiness zones 4-8 or Sunset growing zones 2-10 and 14-24. Gets 1.5 feet tall and a little less wide. Leaves form a clump that produces spikes of drooping bell flowers that are yellow and brown. Grows best in zones 2-10 and can take full sun or light shade, needs well-drained soil, and occasional deep watering for best performance. Varietal 'Sunset' is a dwarf selection.

Digitalis parviflora (Small-Flowered Foxglove, Chocolate Foxglove, Milk Chocolate Foxglove, Spanish Foxglove)
Endemic to northern and central areas of Spain, this species forms downy rosettes of green leaves from which flower spikes rise in the spring and early summertime. Flowers are smaller than that of other species in the genus, and are rust-red colored. This species grows well in USDA hardiness zones 4-9.

Digitalis purpurea (Common Foxglove, Purple Foxglove, Fairy's Gloves, Lady's-Glove, Witch's Fingers, Fairy Thimbles)
This biennial or short-lived perennial does best when grown in USDA hardiness zones 4-9 or Sunset growing zones A2, A3 and 1-24. IT has an erect habit and grows to 4 feet or taller. Purple flowers bloom on one side of 1-2 foot spikes. This species is known as an invasive in the United States (Washington, Oregon, California) and New Zealand. Strains are outlined below.

'Camelot'
3.5-4 feet tall, takes sun or shade and has flowers in lavender, rose, white or cream. Flower throats are speckled.

'Escelsior'
Grows to 5 feet tall and has flowers held horizontally, showing off specked throat.

'Foxy'
To 3 feet tall, strain of annuals that bloom from seed in 5 months.

'Gloxiniaeflora'
4 feet tall, with larger flowers than the species.

'Peloric Mixed'
To 3 feet tall, with a terminal cupped flower.

'Shirley'
6 foot strain that comes in a variety of colors.

Digitalis sceptrum (Isoplexus sceptrum) (Sceptre Foxglove, Bush Foxglove, Madeiran Foxglove)
This tender evergreen shrub reaches up to 6 feet tall at maturity and is native to Madeira. Leaves are large and green, and flowers are yellow, orange, or rust-colored, often seen with chocolate-brown veining. Blooms appear in summertime. These plants prefer woodland habitats, cloud forests, and steep sloped areas. This species takes five years to flower from seed and grows well in USDA zones 9a-10b.

Digitalis thapsi (Mullein Foxglove, Spanish Foxglove)
This perennial species grows best in USDA hardiness zones 3-9 or Sunset growing zones 2-10 and 14-24 and is native to Spain's Iberian Peninsula. Gets to 1 foot tall and wide, and has short spires of drooping purple flowers. Variety 'Spanish Peaks' is an outstanding cultivar of the species.

Digitalis viridiflora (Green Foxglove, Green-Flowered Foxglove)
This perennial species produces yellow-green flowers and is adaptable to partial shade. Flowering stems reach up to 32 inches tall, and blooming is most profuse in summertime. Green Foxglove is native to the Balkans, and foliage is covered in soft hairs. Best in USDA hardiness zones 4-8.

Caring for Digitalis

Take care when planting these beauties in your garden, however, as all parts are poisonous if they are ingested. Plant Digitalis flowers in fall for blooms the next springtime and summer. They can be purchased as nursery specimens or started from seed, either direct sown or started indoors between April and July in most regions. Previous year's seedlings or larger plants can be installed in April or May. Spring-sown seedlings can be planted out in fall. Space plants 2 feet apart for best coverage and airflow. Some species are so tall that they will need some protection from strong winds as well as stakes to remain standing throughout the blooming period. Install stakes at the time of planting. Make sure that your Digitalis flowers are in a spot in the garden that will receive full sun to partial shade. They will bloom best in full sun, but in warmer climates they do appreciate afternoon shade. They prefer rich, well-draining soil that has a pH of between 5.5 and 6.5 (slightly acidic). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Water new plantings regularly as they establish a strong root system. At maturity, Foxgloves require moist soil to flower well. In general, water every time the top inch or two of soil feels dry to the touch. Digitalis is best irrigated with a drip line. They should not be watered from overhead, as doing so will encourage fungal diseases. After planting, mulch around the base of plants to increase soil moisture retention, maintain soil temperatures, and suppress weed growth.

Each year in springtime, apply a 2-inch layer of organic compost around the planting area to improve soil structure, drainage, and nutrient load. This feeding should be sufficient to provide these flowers with enough nutrients to get through their growth and flowering seasons. Fertilizing these plants is rarely necessary; they do not like high-nitrogen fertilizers. To prune Foxglove, cut off the main flower spike after blooms fade, and the plant will send out side shoots that will produce more flowers. Plants will typically die off in summer heat, especially in hot areas; they begin to wilt in temperatures over 90 degrees Fahrenheit. Plants will self-sow freely, but resulting flowers will be white or light-colored, as many garden plants are hybrids. If you do not want Foxglove seedlings in the garden, make sure to prune off the flowering spikes before they set and release their seeds. Plants can be pulled after their flowering year has passed; they will not flower again.

Growing Digitalis in Containers
Foxglove plants can be grown in large, sturdy containers. Before planting, ensure that your container is clean and has adequate drainage holes. Digitalis plants do not like to have their roots in standing water, so soil needs to be well-draining and water needs to be able to vacate the pot through holes in the bottom. If using a regular potting soil mix, make sure to amend it with plenty of compost and organic matter before installing plants. Water Digitalis well in this situation; pots tend to dry out faster than in-ground plantings. A good rule of thumb is to irrigate every time the top inch of soil is dry to the touch.

Harvesting Digitalis Flowers
Foxglove plants are fast growers, and generally flower in their second season (though some cultivars, such as Digitalis purpurea 'Camelot' and 'Foxy' will produce flowers in their first year). Most plants purchased from nurseries are already in their second year, and can be considered annuals. They produce 2-5 foot tall flower stalks packed with beautiful flowers that are wonderful in cut bouquets and arrangements. They have a very pleasant, subtle smell. When out in the garden to harvest flowering stalks for arrangements, make sure to have a bucket of cool water at hand to drop stems into immediately after severing them. Strip the leaves off of the portion of the stalk that will be under water. The vase life for most varieties is between 6 and 8 days.

Propagation

Digitalis, or Foxglove, flowers are best propagated by seed. Please keep in mind that all parts of the Digitalis plants are toxic, and ingestion of plant parts is toxic to humans and animals. Take care to prevent poisoning. To propagate your Foxglove, follow the instructions below:

Propagating Digitalis by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant, especially if you are propagating a hybrid variety. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
Harvest your seeds. The seed heads on plants are pretty easy to spot, they're left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release their seeds. Once they have been released, take them out of the bag and put them in a container so you can work with them. Seeds are viable for about two years when stored properly.
Seeds can either be sown directly into the garden or be started indoors. To start seeds indoors or in a greenhouse environment, first get your container prepared. Next, water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 14-21 from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Foxglove seeds are contained inside of flower receptacles after blooms have faded.

Foxglove seeds are very tiny and brown.

Foxglove grown from seed does not flower until its second year.

Problems and Pests

Certain species of Digitalis are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Digitalis, or Foxglove, is a relatively problem-free plant for garden beds, though they can sometimes have issues with the following pests and diseases: