Many gardeners purchase common foxgloves as second-year potted nursery plants to ensure flowering, but it is also possible to start them from seeds. Planted from seeds, the plants usually don’t flower until their second year, but foxgloves freely self-seed, creating a sustained patch that produces flowers every year. There are also some cultivars that are bred to bloom in their first year from seed, though this doesn’t always hold true. Be aware that foxglove is a seriously toxic flower, both to humans and to pets. The flowers, seeds, stems, and leaves all contain chemicals that can affect the heart. If you choose to plant from seeds (a much more economical approach), be prepared for the plants to take a full year to get established before flowering in their second season. While some seed varieties are bred for first-season blooms, this can be a hit-or-miss proposition. Foxgloves are fairly easy plants to grow in moist, rich soil in full sun to partial shade. Foxgloves come in different sizes and should be spaced accordingly, but as a general rule, it is good to space them about 2 feet apart. Stake the taller types to prevent them from flopping over in a wind storm. They can become somewhat scraggly after flowering is complete, so the plants are often pulled from the garden at this point—or immediately after the seeds have scattered themselves in the garden.
Light
Grow foxglove plants in a full sun to partial shade location. Tailor the amount of sunshine you give this biennial to your climate. If you live in the south, give it some shade, as full sun will be too hot for the plants. In the north, it will thrive in full sun, though some shade is tolerated.
Soil
Foxgloves like rich, well-draining soil that’s slightly acidic, with a pH of 5.5 to 6.5.
Water
Foxglove is susceptible to crown rot, so provide it with good drainage. Keep the soil moist, but not soaked. If there is a dry period in the summer and it hasn’t received 1 inch of rain in a week or the top 2 inches of soil is dry, water the plant thoroughly with a drip hose. Avoid overhead watering, which can encourage fungal disease.
Temperature and Humidity
Foxgloves tend to do better in cooler temperatures and may wilt in temperatures over 90 degrees Fahrenheit. Planted seeds will germinate when temperatures reach between 70 and 80 degrees Fahrenheit. Foxgloves are not fussy about humidity, though excessive humidity may encourage some fungal diseases. Provide good air circulation by giving them sufficient spacing.
Fertilizer
A 1-inch layer of well-decomposed mulch usually provides sufficient nutrients for foxgloves. In good soil, fertilizer is rarely essential and excess nitrogen can actually harm the flower growth. However, if your soil is very poor, you can add a small handful of slow-release 5-10-5 fertilizer in the early spring. Scatter it around the plant and then water over the fertilizer to help it settle. Avoid having the fertilizer touch the foliage, as it may burn the plant.
Foxglove Varieties
Common foxglove (Digitalis purpurea) has several popular cultivars:
‘Goldcrest’ has yellowy-peach blooms and lance-shaped dark green leaves.‘Candy Mountain’ boasts bright, rosy-pink flowers; this variety faces upwards rather than nodding down.‘Pam’s Choice’ has white flowers with burgundy throats.‘Rose Shades’ has two-toned flowers, featuring rose and white blossom spikes.‘Foxy’ is a shorter cultivar (27 inches) with purple, white, and pink flowers. It often blooms in its first year.‘Camelot’ blooms fairly reliably in its first year, producing cream, lavender, rose, and white flowers on 28- to 40-inch stems.‘Excelsior group’ is a very popular group of 4- to 6-foot hybrids in several colors. They are best for zones 5 to 9.
There are also some hybrid foxgloves to consider:
Digitalis × mertonensis (Merten’s foxglove, strawberry foxglove) is a cross between D. purpurea and D. grandiflora, producing a short-lived perennial species (three to four years) with pink flowers.Digiplexis is a hybrid of D. purpurea and Isoplexis canariensis, the Canary Island foxglove. Its flowers are purplish-pink on the outside, with yellow throats with burgundy spotting on the inside. It, too, is a short-lived perennial.
Pruning
As a general rule, deadheading the early flower spikes after the blooms have faded often results in a second, lesser flowering period. However, if you wish for the plants to self-seed in the garden, then leave some flower spikes in place to cast their seeds.
Propagating Foxglove
Foxgloves are generally propagated from seeds collected from the flower heads after the blooms have faded. Foxgloves seeds mature on the stalk and are ready to harvest by mid to late summer. Make sure to do it before the seed capsules have burst and spread seed around the garden.
Overwintering
Common foxgloves can be pulled up and discarded after blooming ends in late summer, as they generally do not return again. First-year plants that have not bloomed, however, should be covered with a thick layer of dried leaves or mulch after the ground freezes in late fall or early winter to moderate soil temperatures over the winter. Make sure to remove the mulch promptly in the spring to avoid crown rot. If you wish, you can leave a few old plants in place to allow them to self-seed in the garden. In the spring, these older plants should be pulled out and discarded, as they won’t bloom again. Caution: Wear gloves when handling foxgloves, as it is possible to absorb small amounts of toxins through the skin.
Common Pests & Plant Diseases
Common foxglove can be prone to attack from insect pests including aphids, mealy bugs, slugs, and Japanese beetles. Mild infestations are often handled by predatory insects, but serious infestations can be treated with insecticidal soaps or chemical spray pesticides. Foxglove can also be affected by a variety of funguses, such as powdery mildew, verticillium wilt, and leaf spot. Minimize these problems by giving the plants good air circulation and making sure they are planted in well-draining soil. Treat seriously affected plants with spray fungicides. Crown rot can be a problem, sometimes caused by white fungal spores or by dense, poorly draining soils. Seriously affected plants will need to be discarded.
How to Get Foxglove to Bloom
If a common foxglove is in the second year of its lifecycle, it generally blooms. Failure to bloom (or poor blooming) is usually due to one of the following:
Plant is in its first year of growth: Foxgloves are biennial plants that generally do not bloom until the second year. Be patient; your plant may bloom the following spring. Plant gets insufficient sun or water: A foxglove that doesn’t get at least a few hours of sun per day, or that doesn’t get at least 1 inch of water per week, is often stingy with its flowers. Plant gets too much fertilizer: Foxgloves respond badly to too much feeding. Unless your soil is rather poor, foxgloves generally don’t need much, if any, artificial fertilizer.
Common Problems With Foxglove
Foxglove is a fairly easy plant to grow, but a couple of common problems are worth mentioning:
Foxglove Plant Has No Flower Spikes
While most nursery plants are grown so they are ready to flower in your garden, it’s possible that you have purchased plants that are still in their first year of growth. If your plant produces just a basal rosette of leaves but no flower spikes, leave it in place until the next year; there’s a good chance that it will flower robustly in its second year of growth. This is also the normal pattern for seeds planted directly in the garden—they don’t flower until their second year of growth. Less commonly, a biennial foxglove that has already flowered will persist over winter and come back in a weak form for a third year. These third-year plants almost never flower and should be pulled up and discarded. Remember, though, that this is true only of biennial varieties. There are some true perennial foxglove species that should be left in place year after year.
Plants Look Shabby as Summer Progresses
It’s fairly normal for foxgloves to begin to look unkempt as the heat of summer arrives. The flower stalks, especially, can look quite shabby. At this point, you can clip off the flower stalks down to the basal rosette (saving the seeds, if you wish). With the flower stalks removed, you may stimulate the plant into producing a second flush of flowers, which often appears as the weather cools in early fall. Or, you can simply pull the entire plant from the ground once flowering is complete. Make sure, though, to remove only the second-year plants that have completed their flowering cycle. You don’t want to pull out first-year seedlings, as these need to overwinter in order to reach their second-year blooming cycle.
Digitalis grandiflora (large yellow foxglove) is a 2- to 3-foot tall native of Central Europe, hardy in zones 3 to 8. Its yellow flowers appear in late spring.Digtalis obscura (willow-leafed foxglove) is a short (1- to 2-foot) native of Spain that produces orange or greenish-yellow flowers in late spring. It is hardy in zones 4 to 8). Unlike most foxgloves, it has a good tolerance for drought.
By far the most common perennial type in North American gardens is the large yellow foxglove (D. grandiflora), which is easily identified because the flowers are a solid yellow, without the multiple colors found in the biennial forms. If your foxglove has speckled colors in its throat, it is almost certainly a biennial form that can be removed once the flowers are gone.
