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
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.
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
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
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.
5 best foxgloves for a wildlife garden
Our native wild
foxglove Digitalis purpurea
D. purpurea alba