DESIGNING A MIXED BORDER
A mixed border, as distinct from an old-fashioned herbaceous border, offers the opportunity to use the greatest range of plant material and gives the longest season of interest. Start with bulbs and early perennials in spring, then summer bulbs and later perennials. Add good half-hardy annuals to take the season through to late autumn, then use evergreen shrubs and hellebores to keep the interest going in winter. Consider shape, colour and texture when planning plantings, along with height, flowering period and foliage.
Shrubs:
Bupleurum fruticosum
Fatsia japonica
Mahonia x media ‘Charity’
Cleome spinosa
Cosmos bipinnatus
Nicotiana sylvestris
Nicotiana langsdorfii
Monarda x hybrida ‘Lambada’
Early summer:
Verbascum ‘Southern Charm’
Aquilegia vulgaris
Achillea
Hemerocallis
Euphorbia characias ssp. Wulfenii
Late summer:
Schizostylis coccinea
Helenium autumnale
Phygelius capensis
Phlox paniculata
Echinacea purpurea
Actaea (Cimicifuga) simplex
Anthemis tinctoria
Lobelia tupa
‘Everlastings’:
Verbena bonariensis
Geranium ‘Bill Wallis’
LATE SUMMER BORDERS
Colour in the late summer border comes principally from perennials and annuals, although some shrubs contribute too. Callicarpa bodnieri 'Profusion', a rather undistinguished shrub, produces masses of vivid purple berries. Hardy fuchsias are at their best now, and there are a larger range of varieties than might be supposed. The graceful Fuchsia magellanica 'Versicolour' is hard to beat and fits into the garden scene better than the larger flowered hybrids; 'Sharpitor' is excellent too. Abelia x grandiflora begins producing its pink flushed white flowers in August, and its neat evergreen leaves are an asset to the border throughout the year.
True blue is relatively uncommon amongst plants, but a trio of shrubs pull off the trick at this time of year. Ceratostigma plumbaginoides is technically a shrub, but is low growing and behaves more like a perennial. Its glowing blue flowers gain in intensity as the leaves change to crimson as autumn advances. C. willmottianum is more shrub-like at around 3ft, with attractive bristly stems. Caryopteris x clandonensis is a good front of border shrub with panicles of blue flowers in late summer. 'Kew Blue' is darker than the species; 'Worcester Gold' has yellow leaves, providing the classic blue/yellow colour partnership in one plant. There are varieties of ceanothus which flower from spring to autumn. 'Autumnal Blue', 'Gloire de Versailles' and 'Burkwoodii' all produce their glorious flowers at this time of year.
Many salvias are tender in all but the warmest gardens, including the lovely Salvia patens but the much under-rated S. officinalis ' Purpurascens Group' is terrific, completely hardy and not only provides year-round interest but combines so well with many other plants. The forms of S. greggii and S. microphylla var. microphylla are hardy and long flowering too. Tender salvias are easily raised from cuttings and it is worthwhile to over-winter plants in this way for the extra interest they provide.
Bupleurum fruticosum is an unusual shrub with green umbellifer flowers over a long season; it is easily raised from seed. Clerodendrum trichotomum is a large shrub with brilliant turquoise berries, but C. bungei is one of the stars of the autumn border. With large, dark, purplish leaves, and rounded heads of sugar-pink flowers, this beautiful and uncommon shrub behaves more like a perennial. It has a suckering habit.
PERENNIALS
The following are all great plants for the late summer/autumn border:
Eupatorium purpureum (Joe Pye Weed)
" cannabinum (Hemp Agrimony)
Rudbeckia nitida 'Herbstonne'
Gaillardia aristata
Helenium autumnale
Heliopsis scabra
Anemone x hybrida (Japanese Anemone)
Monarda hybrida 'Lambada'
Cimicifuga simplex Atropururea Group - now more properly Actaea
Papaver ruprifragum
Veronicastrum virginicum (Bowman's Root)
Persicaria amplexicaule 'Firetail'
Sedum 'Purple Emperor' - and many others
Dahlia - in variety but especially 'Bishop of Llandaff' & 'David Howard'
Schizostylis coccinea (Kaffir Lily)
Zauschneria californica
Verbena bonariensis
Verbena rigida
Perovskia atriplicifolia (Russian Sage)
Agastache foeniculum (syn. Anisata) (Anise Hyssop)
Asclepias tuberosa (Butterfly Weed)
Macleaya cordata
Penstemon - in variety but especially 'Firebird' ('Schoenholzeri') and 'Garnet' ('Andenken an Friedrich Hahn')
Aster amellus
Aster novae-angliae (Michaelmas Daisy)
Lobelia tupa
Lobelia bridgesii
Verbascum 'Southern Charm'
Diascia rigescens
Echinacea purpurea (Purple Coneflower)
Liatris spicata
Tricyrtis formosana
Physostegia virginiana (Obedient Plant)
Erodium manescavii
Phlox paniculata
ANNUALS
There are also a number of annuals which help to keep the border filled with colour until the end of October:
Tithonia 'Torch' (Mexican Sunflower)
Cleome spinosa
Nicotiana sylvestris
Nicotiana langsdorfii
Calendula officinalis
Cosmos bipinnatus
Cosmos sulphureus
Rudbeckia hirta 'Prairie Sun'
Alonsoa warscewiczii
Amaranthus caudatus (Love Lies Bleeding)
Mirabilis jalapa
Rehmannia angulata
Scabiosa 'Chat Noir'
Cerinthe major 'Purpurascens'