Digitalis, better known as foxgloves, are among the most impressive of the tall perennials in any garden setting. Cottage gardens especially owe much of their charm to these statuesque, bumblebee-friendly flowers. (Foxes have nothing to do with them other than inspiring their whimsical name.)
Despite their charm, foxgloves have a reputation for being difficult to cultivate. They grow easily but can be tricky to sustain if you’re unfamiliar with their quirky lifecycle. Fortunately foxgloves can be managed successfully if you know what you’re dealing with. I’ll try to dispel some of the mystery here, and provide a few tips.
You might know foxgloves as the source of the first heart medication digitalin, once used to regulate the human pulse and for treating epilepsy. Today these uses are no longer considered appropriate or safe, and the plant should never be ingested in any form. Digitalis is highly poisonous to humans, cats, dogs and horses. If you have pets or kids who like to sample plants unsupervised, foxgloves are best left out of the garden.
Foxgloves comprise about twenty species worldwide, plus hybrids. They originated in Europe, western Asia and North Africa. Digitalis purpurens is the main species from which most ornamental hybrids descend. More about those in a minute.
Two true perennial species are widely available: Digitalis grandiflora (a soft yellow) and digitalis x mertonensis (a dusty pink). These two are much shorter than the hybrids, about 24″ tall, and will readily self-seed if allowed. They work well in pastel color schemes in part sun and are fully hardy in zone 6.
However, the perennials are still rather short-lived. If you get a few years out of them you’re doing great. They bloom in May here. Since they generally come true to seed, longevity is not a problem. By all means, feel free to grow these more demure forms.
Most of us want to grow the showier hybrids though, and they can be tricky. So that’s what I’ll focus on here.
Perennial vs. Biennial
The rub is that nearly all other digitalis cultivars are biennial hybrids, not perennial — meaning they live just two years. They form basal rosettes of medium-green fuzzy foliage the first year, waiting until the following summer before throwing up their spires of bloom and dying.
Some strains like the Dalmations(spotted) are bred to bloom the first year, but most don’t. For example the popular Excelsior strain and most Camelot hybrids are second-year flowering. Either way, this two-year cycle creates a never-ending longevity issue for the gardener. We’ll talk about overcoming this further on.
Cultivars I Especially Like
I admit, I love all foxgloves regardless of cultivar. Despite this I’ve actually grown a rather limited collection, so I’ll stick with what I know from experience.
Snow Thimble – My favorite foxglove, Snow Thimble is a pure icy white that simply glows, especially at dusk. This cultivar is very hardy with robust vigor and several spires per plant. It’s not as showy as some, but to my eye it’s the classic foxglove one sees in English gardens: elegant and beautiful. Its exceptionally white coloring “cools” the garden palette.
Dalmation strain (photo at very top) – Of course they’re spotted, and were bred to bloom their first year. A bit more compact than most, these charmers top out at 30 inches, making them especially versatile. They come in three lovely colors: peach, purple and cream. I’ve grown purple and peach, but I inadvertently bought second-year plants, so I didn’t get two years out of them. Be sure to ask before buying! It’s often hard to tell the age of nursery plants.
Pam’s Choice – An arresting white hybrid washed with a deep burgundy throat. Stunning!
Sugar Plum – Raspberry pink with a burgundy throat. Makes a great companion to Pam’s Choice. Both bloom second year only.
Candy Mountain – Deep apricot-pink with upward-facing bells, this sterile hybrid blooms for months. Fat and bold with saturated coloring, there’s no missing it in the garden. I grew it at my previous property and was amazed at its vigor. Bees ignore it though, so not a good choice for attracting pollinators.
Rusty Foxglove (digitalis ferringea) – A 6-foot variety with rusty-veined, peachy buff flowers best for back of the border or meadows. I’m in the process of growing this for the first time. I had two plants, but lost one over the winter. The survivor is beginning to bud up now. I’ll let you know in a later how it turns out. Here’s what it should look like once it’s in flower.
(photo courtesy of Annie’s Annuals)
Update, June 2023 — Here is what came up and finally bloomed from my remaining plant, which I thought was digitalis ferringea:
Surprise! A very pleasant one, too.
As you can see, it is not Rusty but Woolly, also known as Grecian foxglove, digitalis lanata. The lower part of each flower is elongated, like a custom landing pad for bees, and white in color. Each bell has goldenrod veining inside. It is also much shorter, about 26″ tall. This one is so pretty, with narrow neat foliage and excellent proportions.
Apricot Beauty (for experienced gardeners). This is an incredibly beautiful cultivar, but so far I’ve had poor luck with it. I lost both of my first year plants the winter of 2020-21, probably because they were in too much sun and rather exposed. It does well in California but seems challenged in Pennsylvania. Obviously in our climate, this cultivar must have part shade and excellent winter protection. In other words, you’ve been forewarned. It may do great for you, or not.
But just look at it — who wouldn’t want to try to grow this magnificent variety! I may try it again in a more protected, shadier spot.
(photo courtesy of Floret Farms)
Self-sown volunteers
As if a short lifecycle isn’t inconvenient enough, hybrids don’t come true from seed. Self-sown plants can turn out very similar or revert to their pre-hybrid parentage. Some get crossbred by the bees.
As a result, volunteers can be any combination of pink, cream, yellow, or white, spotted or not. Bells tend to form on just one side of the stem, whereas hybrids usually pack more bells around the stem for a much fuller effect.
The whole plant is slimmed down. Volunteers also tend to have a shorter blooming period. Once the bells are fertilized they wither and drop quickly (from the bottom up). But secondary spikes will prolong the show if you deadhead.
Reversion isn’t a bad thing; just know that self-seeded plants probably won’t look like what you started with.
In woodlands and cottage gardens, naturalized volunteers sit more easily in the landscape than their fancier cousins, and often in much greater numbers. The effect can be just as lovely as the hybrids, if not more so. I love the abundance, frankly.
What to Do About the Short Lifespan?
For continuous flowering year over year, there are three ways to approach growing foxgloves.
Start with first- and second-year plants simultaneously. This sets up a staggered lifecycle between the two groups. (Confirm the age of any plants before you buy. You may have to mail order a few.) This way you’ll always have some in bloom while next year’s batch is developing. Let some set seed to keep the cycle going, deadhead the first spikes to encourage secondary blooming, and weed out the unwanted extras. This low-cost solution works well for informal gardens and semi-wild areas.
Purchase hybrids that bloom their first year such as the Dalmation strain. This approach should allow you to skip replenishment at least every other year, and you can deadhead to avoid self-seeding. However, your choices of hybrid will be limited. If you should lose all your plants over winter, it’s a setback.
Treat like annuals and buy every year. This approach ensures a gorgeous show but is costly and labor intensive. It can be hard to find what you want for sale. Still, for formal borders or wherever you want a precise color scheme, this is probably your best option.
I tend to rotate between all three. I let my hybrids self-seed, and every couple of years I supplement the volunteers with new hybrids, especially varieties I can’t get any other way. This also refreshes the colors, ensuring I’ll get some pinks and purples along with some creamy whites.
There’s no right or wrong here. Do whatever works for you and your budget in any given year. The important part is to make a plan, whatever it is, so you’re more likely to stick with it.
Companions for Foxgloves
Since foxgloves are tall and slim, they look best in groups of three or more. (Flower spikes open from the bottom up.) Pair them with tiger liles, poppies, alliums, bearded iris, tall phlox, peonies and delphinium. Shrubs and conifers make superb backdrops, as do stone walls and tall hedges. Let your imagination run wild!
Annuals and lower perennials like catmint, bellflowers, salvia or cranesbill can be placed in front.
You can mass foxgloves close together because they don’t spread beyond the basal clump. Their verticality makes a nice counterpoint to the rest of the garden. Just keep the background uncluttered so the flowering spires stand out nicely. As an extra precaution, remember to avoid planting close to splash pools and play areas where children could pick them, due to their toxicity.
Soil and Care
Foxgloves prefer part sun to dappled shade in rich, neutral to slightly acid soil with compost or humus mixed in. Avoid all-day sun and exposed locations. They grow fine in amended clay, but they don’t like to sit in wet ground over winter. Foxgloves can get aphids, fungal and bacterial leaf spots, and root rot. I had good luck until this year, when nearly all of mine got a rust-like disease. Rarely have pathogens been a problem until now. Too much rain and excessive heat stressed them, and stressed plants are more vulnerable. Add in high humidity as the climate changes, and it’s a recipe for ongoing problems, I fear. We will have to see.
Normally, healthy basal clumps will stay green most of the year, right into January. After a hard snow or prolonged freeze they do die back, but quickly revive as soon as March rolls around. Tufts of bright green emerge from the center of the seemingly dead rosette. Clear away the brown leaves and watch them take off! Second year plants will not revive the third spring, having ended their natural life cycle.
If desired, you can boost vigor with a light application of granular fertilizer designed to promote flowering. After bloom, cut the main flower spike down to the base, allowing any smaller ones to succeed it and flower. If you let a few spires from the second flush set seed (don’t mulch around them) new rosettes will appear by July/August. But don’t let them all go to seed! These guys can really proliferate and having to weed a lot out of seedlings is the last thing you want.
I leave many in place and move the rest by early September. Timing isn’t critical, but they need a few weeks in their final spot to firmly establish before winter. Water and mulch well.
Because foxgloves are so poisonous, wash your hands after handling them, and be sure to wear gloves if your skin is sensitive.
Can you cut foxgloves for the house?
Yes, but I don’t recommend it due to their extreme toxicity except for special occasions when you really want to make a statement, and the arrangement is inaccessible — an altar, tall pedestal, etc.
If you do cut some, harvest the spires before the bees get to them, or they won’t last in the vase. (Fertilized bells drop quickly.) You might find these tips on arranging helpful.
I do hope you consider growing foxgloves. At least try them for a few years and decide for yourself. You just might fall in love.
