Foxglove plants are biennials or short lived perennials. They are commonly used in cottage gardens or perennial borders. Oftentimes, because of their short life span, foxgloves are planted in succession, so that each season a set of foxglove blooms. However, not preparing them properly for winter can throw this succession planting off and leave the gardener with empty gaps in the garden. Continue reading to learn about winterizing foxglove plants.
Foxgloves can be a source of much frustration for the gardener. I frequently talk with customers who are upset about having lost their foxglove, wondering what they did wrong to kill it. Many times it’s nothing that they did wrong; the foxglove plant just lived its life cycle and died. Other times, customers come to me concerned about why their foxglove grew leafy foliage but did not flower. The answer to this, too, is just the plant’s nature.
Biennial foxglove usually does not bloom its first year. During its second year, it blooms beautifully, then set seeds and dies. True perennial foxglove, like Digitalis mertonensis, D. obscura, and D. parviflora may flower each year but they still only live a few short years. However, they all leave behind their seeds to carry on their beautiful legacy in the garden. Furthermore, knowing how to care for foxglove in winter can help ensure additional blooms each season.
It is very important to note that foxglove is a toxic plant. Before doing anything with foxglove, be sure you are wearing gloves. While working with foxgloves, be careful not to put your gloved hands on your face or any other bare skin. After handling the plant, wash your gloves, hands, clothes and tools. Keep foxglove out of gardens that are frequented by children or pets.
Most foxglove plants are hardy in zones 4-8, with a few varieties hardy in zone 3. Depending on variety, they can grow 18 inches (46 cm.) to 5 feet (1.5 m.) tall. As gardeners, it is in our nature to always keep our flower beds neat and tidy. An ugly, dying plant can drive us nuts and make us want to run right out and cut it down. However, too much fall preparation and cleanup is often what causes foxglove not to survive winter.
In order to have more foxglove plants the next year, the flowers need to be allowed to bloom and set seed. This means no deadheading spent flowers or you will not get seeds. Naturally, you can buy new foxglove seeds each year and treat them like an annual, but with patience and tolerance you can also save a little money and let your foxglove plants provide their own seed for future generations of foxglove plants.
After the plant has set seed, it is ok to cut it back. Biennial foxglove will set seed its second year. The first year, it is ok to cut the plant back when the foliage begins to die back because there is no flower or seed production. Perennial foxglove plants should also be allowed to set seed for future generations. After they produce seed, you can collect them to sow indoors in early spring, or leave them to self-sow in the garden.
When winterizing foxglove plants, cut first year biennials or perennial foxglove back to the ground, then cover the plant crown with a 3- to 5-inch (8-13 cm.) layer of mulch to insulate the plant through winter and help retain moisture. Unprotected foxglove plants can dry out and die from the brutally cold winds of winter.
Foxglove plants that have grown throughout the garden from natural self-sowing can be gently dug up and replanted as needed if they are not exactly where you want them. Again, always wear gloves when working with these plants.
Foxglove is the towering giant in a flower bed, with some varieties growing up to 5 feet. They are a biennial plant, which means they bloom in their second year with beautiful, bell-shaped flowers, and then die. They reseed easily, so if you want flowering plants every year, plant foxgloves two years in a row. They bloom in a variety of colors, and each plant's offspring will produce multi-colored flowers. The first year, a foxglove will produce leaves, but no flowers.
The foxglove is best planted at the back of your flower bed, otherwise it will block everything behind it. As long as the soil is rich and drains well, foxglove can also be planted along walkways and trees. You should, however, keep foxglove out of areas where children play, as it is highly poisonous if ingested.
TIP: Our expert gardening advisor Karen Thurber adds, "Besides being a beautiful flower in the garden, foxglove is also a medicinal plant. Digitalin is extracted from the leaves and used in multiple medicines to treat heart conditions."
Here are some tips for growing healthy foxglove plants.
When you are shopping for foxglove, look for plants that have many healthy looking leaves. Make sure you buy one that is already a year old, so you will have blooms that year. Avoid containers with multiple seedlings as these will need two seasons to bloom.
The foxglove likes full sun, but in warmer climates it should get some shade in the afternoon. Generally, the foxglove prefers cooler climates, like zones 4 to 8. If you are planting it outside of a prepared bed, look for a spot that has rich, slightly acid soil with good drainage. It should be planted while temperatures are still slightly cool.
Foxglove prefers a rich soil, but can be planted in less rich soil as long as you add compost and mulch the area well. If the soil has poor drainage, you may need to add amendments to improve it.
Dig a hole for the foxglove and put a handful of compost into the hole. Add the plant to the hole and gently firm the soil around it. Water the plant, then add a thin layer of mulch. Use mulch like lucerne straw. This will protect the plant from slugs and snails. The plant needs to be fertilized, usually in early spring.
Because of their height, foxgloves may droop under their own weight. You can help support them by tying them to a stake or by straightening a clothes hanger, inserting the straight end into the ground, and wrapping the hook around the plant to hold it up.
When the flowers begin to fade, cut the spike from the foliage. This will encourage new shoots from the sides.
TIP: Karen notes, "Foxglove blooms in late spring to early summer."
When the plants die, lay the dead plant on the ground where you want more to grow. You can also manually remove the seeds and sprinkle them in the appropriate area.
The following is according to Burpee, which sells Foxglove seeds and plants. Among the type of speckled foxglove seeds they sell is Excelsior, above, which grows 5 feet tall and comes in pink, rose, purple, cream, primrose and white. Foxgloves, along with delphiniums, are the stars, the bones of the classic cottage garden. Burpee says:
Direct sow in rich, moist soil in part shade to full sun after danger of frost. Remove weeds and work organic matter into the top 6-8 inches of soil then level and smooth. Sow seeds evenly and thinly and barely cover with fine soil. Keep evenly moist. Seedlings will emerge in 14-21 days depending on soil and weather conditions. Thin to stand about 18 inches apart when large enough to handle.
Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their germination. Mulches also help retain soil moisture and maintain even soil temperatures. An organic mulch of aged bark or shredded leaves lends a natural look to the bed and will improve the soil as it breaks down in time. Always keep mulches off a plant’s stems to prevent possible rot.
Careful watering is essential in getting plants off to a good start. Water thoroughly at least once a week to help new roots grow down deeply. Soil should be damp at about 1 inch below the soil surface. You can check this by sticking your finger in the soil. Water early in the morning to give all leaves enough time to dry.
One inch of rain or watering per week is recommended for most perennial plants. You can check to see if you need to add water by using a rain gauge.
Until plants become established, some protection from extreme winds and direct, hot sunlight may be necessary. Good air movement is also important. After new growth appears, a light fertilizer may be applied. Keep granular fertilizers away from the plant crown and foliage to avoid burn injury. Use low rates of a slow release fertilizer, as higher rates may encourage root rots.
In general, there is no need for staking.
Mulch after the ground freezes in fall to prevent heaving in winter. Evergreen branches work well for this. Remove mulch in spring when new growth appears.
You may start from seed or purchase nursery plants.
Seeds yield variable results, because seeds from hybrids do not replicate the traits of parent plants, and may even be sterile.
Nursery plants provide more certainty as to what you are going to get, with knowable characteristics.
To propagate foxgloves this way, you’ll need to purchase seeds or collect them from a friend’s plant.
Learn how to save foxglove seeds for next year in this guide (coming soon!).
You can direct sow seeds in the garden after the danger of spring frost has passed.
Moisten the soil and sprinkle several seeds every 12 to 18 inches. Do not cover, as they need light to germinate.
Maintain even moisture for the next two to three weeks while seeds germinate.
When seedlings have two or more sets of true leaves, thin them out to a distance of 12 to 18 inches to accommodate mature dimensions.
Proper spacing promotes good air circulation and inhibits fungal disease.
Alternatively, start seeds indoors six weeks before the last average spring frost date and transplant them to the garden after all danger of frost has passed.
Before you plant out, acclimate seeds started indoors to the outdoors.
To do this, set them outside in a sheltered, partially shaded place for a few hours each day for four or five days.
Take care not to overwater them to avoid damping off, a fungal disease that thrives in cool, wet environments and kills seedlings.
Transplant the seedlings to the garden at 12- to 18-inch intervals. Keep the soil level of the seedling container even with the ground soil level to minimize transplant stress.
Tamp the soil gently around the seedlings and water them in well.
You may also direct sow seeds in late summer, at the same time they would naturally disperse.
Transplant from nursery pots to the garden after the last average spring frost date has passed.
If your nursery sells plants in late summer to early fall, you can also plant them out then.
To transplant, carefully work the plants out of their containers.
Set them into the soil so that the surface of the pot soil is even with the ground soil surface, for a smooth transition. Maintain spacing of 12 to 18 inches between plants.
Tamp the soil down around the plants and water in well.
Keep in mind that some cultivated varieties behave as annuals and bloom in the first year, while others are biennial or short-lived perennials that bloom the second year after experiencing a winter chill.
In addition, note that plants may cross-pollinate in the garden, causing color dominance or variations in the next generation.
Additionally, sometimes plants that bloom in the first year may bloom again in the second, so you may want to keep the plants in place at season’s end.
The foxglove plant has been around for centuries and stories of how it got its name are just as colorful as its flowers. The name ‘foxglove’ seems to derive from one of two stories told in Scandinavia.
The first one tells of fairies saving the foxes from extinction by showing them how to ring the digitalis bells to warn their kind of the danger of approaching hunters. The second tells of foxes putting on florets as gloves so their steps would be quieter when approaching the chicken coop.
In Wales, digitalis was called Goblin’s Gloves because it was believed that hobgoblins wore the long bells on their fingers and they would impart magical elements to the wearer.
‘Foxy’ mix planted with delphinium. Photo courtesy of Goodness Grows
Common foxgloves are biennial plants, which means that unlike perennials, which come back each year, and annuals, which last only a single season, the plant takes two years to fully flower before finishing its life cycle. "Most people misunderstand the nature of foxgloves, expecting them to behave as their perennial plants would and reliably bloom year after year," says Dooling. Look for your plant to grow "a rosette of foliage in its first season before developing tall spikes of large, bell-shaped flowers in the second season," says Dooling. "First year rosettes can be moved throughout the season easily, so you can enjoy their flowers the next season where you want them."
Between the first and second season, the plants need to spend four to six weeks at temperatures between 38 and 45 degrees to encourage new flowers—a process called vernalization. "Many outdoor garden conditions will provide this," says Dooling, "provided there is ample drainage and protection from winter damage." If you're hoping to grow foxgloves that mimic the dramatic versions at flower shows or botanical gardens, though, you'll need a controlled setting, like a greenhouse—or a specific cultivar. "In recent years, many new cultivars have entered the market that do not require vernalization, making them easier to grow—an amenable choice for both growers and the home gardener that does not have a range of greenhouses," says Dooling.