Grow the Foxglove Family


It is well known amongst experienced wildlife gardeners that there are certain groups of plants that are special insect attractants.  Sometimes every plant in a family is designed to be pollinated by insects; in other groups there may be the odd one or two plants that are special in this way.  If a family of plants attracts insects in abundance and has a great range of beautiful garden worthy flowers, including a few natives, we are on to a winner.  Generally these special plants are unadulterated in their structure – single blossoms rather than double, and many are wildflowers in their native homeland.  The group we are looking at here is composed of both British natives and non-native wildflowers, mostly from Europe, but it is rather exceptional that this group also includes a range of colourful varieties of great garden flowers that have been derived from natives, yet they still retain their wildlife attracting properties.  

Foxgloves are exceptional plants for wildlife, their only fault being that the type of wildlife they attract is within a rather limited range.  However, if you want to bring bumblebees of all shapes and sizes to your garden you could do no better than grow a selection of these stately and imposing plants.  They are occasionally reported as being butterfly attractants but one only has to look at the shape of the flower to see that this is unlikely, in spite of the nectar they produce.  Some moths however, do technically have tongues long enough to reach into the smaller flowers of the perennial species but I have no personal observations of this activity.  There are a few moths that use the leaves of foxgloves: the tiny and delicate foxglove pug moth is named after its larval food plant and the caterpillar of the frosted orange moth also eats the leaves.

All foxgloves have a similar flower shape – a tall spike of hooded flowers either confined to one side of the spike, like our own native ‘fairy thimbles’ as it was called in the past, or some of the perennial species have flowers all the way around the spike.  The individual flowers may be 5 cms or more in length, or tiny bells of just 2 cms.  Colours vary from white through pale yellow, peach and russet brown, to the dark pink of our wild foxglove.  Inside each bell are the stamens, positioned to transfer their pollen to the furry backs of the bumblebees that pollinate them while they forage for nectar at the base of the flower.  The spots and lines within the foxglove flowers help to attract bumblebees and guide them to the nectar.  Bumblebees also collect the pollen to feed their young.

Our native foxgloves, Digitalis purpurea, and its varieties  If you have little room for these tall plants try at least to find a space for a couple native foxgloves in their true wild pink form.  The occasional white flowered plant does appear naturally in woodland glades and rides, and these can be very elegant in a shady spot in a corner, brightening it on dull days.  Seed of Digitalis purpurea alba is often available separately in seed catalogues.  Bear in mind the wild plant is a biennial so you will need to allow it to spread by seed if you want to keep it going, or collect seeds and propagate more plants yourself.  This applies to all the varieties of the native foxglove, and there are many of them in the most beautiful range of colours.  My favourite is probably Excelsior hybrids, tall elegant spikes of bells in white, through all shades of pink, most with spotted throats.  Selective breeding in this case has ‘improved’ our native by increasing the number of flowers on each plant – instead of flowers down just one side of the stem they extend from a half to three quarters of the way around the stem.  This variety makes a real statement at the back of a border, flowering from late May into June and sometimes July.

Other special introductions derived from the wild foxglove include the variety called Apricot with flowers in a pale, orangey pink and Primrose Carousel whose bells are a pale yellow with dark spots.  All of these plants make a spectacular show in the early summer garden and although biennial they can be encouraged to flower a second year.  This won’t work with every plant but is well worth trying.  Once flowering has finished and before the seed has properly set, cut the flower spikes back to the basal rosette of leaves.  With any luck these plants will produce another flower spike in the next year.  Leave a few to seed though to make sure your supply of foxgloves continues and increases.

Flowering this month though are the wonderful  'perennials foxgloves'.  These come in a wide range of sizes and colours and are largely natives of southern Europe.  They truly are wonderful plants if you don’t mind their lack of brightly coloured flowers.  The colours tend to be more subtle – pale yellows, browns, russets and creams.  Sizes vary from the relatively dainty Digitalis lutea at about 60 cms (2 feet) to D. ferruginea gigantea which in my garden reaches more than 2 m (6 - 7 feet!) - a very impressive plant with enough flowers to accommodate all the smaller species of bumblebee you are ever likely to have in your garden.  The flowers spikes are enormous and sturdy so they are unlikely to get blown over in bad weather.  There are many species available as seeds but try to see pictures of the plants first if you are likely to be swayed by flower colour.  I love the more subtle tawny shades but they might not be everyone’s taste.  Try D. lanata, Woolly Foxglove (cream flowers with purple veining in the throats), D. lutea (pale yellow flowers) or D. parviflora (chocolate brown flowers).  Digitalis viridis has pale green flowers and D. ferruginea flowers are russet.  There are sizes to suit any garden and which ever species you grow they are bound to be noticed, not just for their unusual colours but they actually hum with bees.

Where to grow them  Foxgloves do not have to be grown in shady spots.  Although our native and its varieties prefer some shade, this is a plant that will grow on cliff tops in full sun.  Semi shade is best though for flower colour, sun drenched plants tending to produce paler flowers and suffering from lack of moisture at their roots.  The perennials are also quite adaptable and most are happy in full sun or light shade, as long as the soil does not dry out excessively.

How to grow foxgloves from seed  Growing foxgloves from seed requires a little skill, simply because the seeds are so tiny.  Once any of the species or varieties are established in your garden they will self seed fairly reliably.  You need only take care not to remove or hoe up all the tiny seedlings which appear late in the summer, or the following spring.  Sometimes it is worth the effort of transplanting a handful of these seedlings into pots or plugs to keep an eye on them – they are less than a mouthful for any slug!  Seed can be collected throughout the summer – even if you forget to do this when the seed is properly dry during the summer months, they is usually a little left in the autumn. Pluck a section of a seed spike and quickly turn it upside down into a paper bag.  This will produce a large quantity of minute seeds which can be stored until you want to sow.  Sow in the early to late spring in pots by covering the surface of the compost with a thin layer of horticultural grit.  Then simply shake the seeds gently onto the grit where they will settle down into the spaces.  There is no need to cover them.  This will help to keep fungus gnats at bay and prevents the seeds from being covered too deeply which is a common reason for failure with tiny seeds. Keep in a warm, light environment until germination occurs and prick out when they are large enough to handle.  Alternatively you can sow thin rows into fine, well raked soil in spring, cover very lightly and plant out into permanent positions in the autumn.

Bear in mind all parts of foxglove plants are poisonous.  Having said that, no wildlife garden should be without a few foxgloves if possible.  The copious amounts of nectar and pollen they produce ensure that many different species of bumblebee will forage amongst them, from the largest queens of the white tailed bumblebee (Bombus leucorum) to the smaller species such as the aptly named small garden bumblebee (Bombus hortorum).  The wonderful foxglove feeds them all.        

The 5 best foxgloves for a wildlife garden

  • Our native wild foxglove Digitalis purpurea
  • D. purpurea Excelsior hybrids
  • D. purpurea alba
  • D. ferruginea
  • D. lanata
 

© Text and photographs Jenny Steel 2017