Japanese anemone (windflower)

Late summer - autumn flowering erect perennial, height to about 2-4ft depending on variety, spread indefinite. Pretty, simple flowers for an informal shady border (not keen on lots of sun). Available in white and pinks. Recommended - "Honorine Jobert", white, probably the best. "Bressingham Glow", pink.

Buddleia davidii

Butterfly bush 

Medium to large shrub, covered in fragrant purple cone-shaped inflorescences 4"-12" long in summer that are in turn frequently covered in butterflies. Flowers of different varieties come in shades from white through lilac to quite dark purple with pinks too. There's also an orange flowered variety B. globosa with golf-ball sized and shaped inflorescences. The star of the group for my money is Buddleia alternifolia, though not as tough or quick as davidii.

Blueblossom

 Evergreen shrub, blue flowers in spring, small mid green leaves about 1-3" long. To 6m (20ft) high and wide, though easily kept in check by pruning. Variety "repens" frequently sold - creeping  blueblossom, height and spread from about 1-2.5m (3-8ft).  

Clematis

montana and tangutica

C. montana - Spring flowering twining deciduous climber with masses of simple 4-petalled flowers in white to shades of pink depending on variety. Not really suitable for a wall, better in 3-dimensions, growing through an old tree, over an out-building, pergola etc. Will go to 25-30ft if unpruned. "rubens", rose-pink, "grandiflora", large white scented, "Mayleen", deep pink, bronze foliage.

C. tangutica - similar in growth habit to C. montana, but flowering in late summer and autumn with small bell-shaped 4 - petalled flowers in all shades of yellow from pale to deep and through to orange depending on variety. Foliage finely dissected and fern-like. Many available varieties "Bill McKenzie" probably the best.

Eucalyptus gunnii

Cider Gum

Actually a tree if left to its own devices that will go to 50ft + if it's happy. However, don't be too alarmed. What you do is you treat it as a coppice stool. Let the plant get established for one or two years and then in Feb / March you cut it down to about 4-6" above ground level. This encourages it to throw out new shoots from just below the cut point. The plant will then provide you with lots of very attractive glaucous blue/green juvenile foliage that can grow up to 6ft from ground level in a season. It's also reputed to keep midges and mosquitoes at bay, so plant it near the patio.

Lavatera

Mallow

Woody shrub or perennial with masses of pink flowers about 3" across over long period in summer. Semi-evergreen, to about 6ft wide and tall given the space, unfussy about position but do better in sun. "Barnsley", pale almost white flowers aging to mid pink. "Bredon Springs", dusky pink, "Rosea", rose pink. Short lived but easy to propagate in early summer.

Prunus laurocerasus

Cherry laurel

Large dense, bushy evergreen shrub. Long glossy leaves to about 6" long, dark green above, lighter below. Fragrant white flowers produced in spring. With the (quite deserved) decline of x Cupressocyparis lleylandii as a hedging plant, laurels should be the ideal replacement. They are dense and fast growing, but respond better to trimming and don't just proceed skywards indefinitely.

A smaller variety "Otto Luyken" grows to about 3ft tall and wide and is suitable for inclusion in a border.

Tough and hardy, a single plant may be grown as an informal wind-break or at the back of a large border where the dark green leaves set off other foliage and flowers admirably.