Aconitum napellus (Monkshood): Dark blue hooded flowers over finely divided foliage. This Aconitum flowers early, in late spring/early summer. Height to 1.5m. Hardy. [Collect Only]

Agastache rugosa 'Liquorice Blue' (Korean mint 'Liquorice Blue'): Spikes of warm blue lipped flowers from late June onwards. Very attractive to bees. Aromatic foliage. To 1.5m. Hardy in light soils. [Collect Only]

Althaea cannabina (Hemp leaved Hollyhock): Very tall, slender, wandy stems with shell pink flowers in late summer

Amsonia hubrichtii (Hubricht's bluestar): Clumps of soft feathery green foliage and palest blue star-like flowers in late Spring. Textural plant. Attractive autumn colour. Up to 60cm. Hardy

Armeria maritima 'Splendens' (Thrift 'Splendens'): Cushion-forming with linear dark green leaves, bright carmine pink flowerheads. Max Height 25cm. Flowers May to June. Full sun. Hardy.

Aruncus aethusifolius (Goat's beard): Lovely fresh ferny foliage which turn golden in the autumn. Spikes of creamy white flowers in early summer. Hardy. Up to 50cm.

Baptisia 'Indigo Spires' (Indigo weed 'Indigo Spires'): Spikes of violet-blue pea-like flowers with a yellow edge above a mound of grey-green foliage. Long flowering. Hardy. Up to 1.2m [Collect Only]

Baptisia 'Purple Smoke' (Indigo weed 'Purple Smoke'): Tall spikes of violet pea-like flowers on almost black stems, attractive grey-green foliage. Dark-grey seed pods. Hardy. Up to 1.2m

Baptisia australis (Indigo weed): Spires of lipped indigo flowers over olive-green foliage. Flowering height 1.2m.

Baptisia australis 'Alba' (Indigo weed - white form): Spires of lipped white flowers over olive-green foliage. Hardy. Flowering height 1.2m.

Deschampsia cespitosa (Tufted hair grass): Summer flowering grass with airy silvery purple flower heads which keep their structure long into winter. Hardy. Up to 1.2m.

Deschampsia cespitosa 'Goldschleier' (Tufted hair grass 'Goldschleier'): Summer flowering grass. Airy golden flower heads keep their structure long into winter. Hardy. Up to 1m.

Deschampsia cespitosa 'Goldtau' (Tufted hair grass 'Goldtau'): Early flowering grass, in flower by mid-July. Airy flower plumes which shimmer if catch the light. Shorter than many varieties.

Deschampsia cespitosa 'Schottland': Summer flowering grass with dark green leaves and airy silvery purple flower heads, keep their structure long into winter. Hardy. Up to 1.2m. [Collect Only]

Dierama pulcherrimum (Angel's Fishing Rod): Tall, wiry, arching stems with soft pink nodding bells. Lovely near water or over paths. To 1.5m.

Dierama pulcherrimum 'Alba' (Angel's Fishing Rod): Tall, wiry, arching stems with white nodding bells. Lovely near water or over paths. To 1.5m. [Collect Only]

Echinacea purpurea 'Green Twister' (Coneflower 'Green Twister'): A new variety with a unusual mix of purple and lime green flowers with upturned petals and a central dark cone. Hardy. Up to 60cm. [Collect Only]

Echinacea purpurea 'Magnus Superior' (Coneflower 'Magnus Superior'): Superb form with tall stems of pink daisy flowers with a central brown cone. Prefers full sun and good drainage. Hardy. Up to 1m. [Collect Only]

Echinacea purpurea 'Rubinstern' (Coneflower 'Rubinstern'): Large pink flowers with a big golden central cone in late summer

Eryngium bourgatii Graham Stuart Thomas's selection (Sea Holly Graham Stuart Thomas's selection): Spiny, violet blue flowers in summer of even spinier blue-green leaves with white mid-ribs.

Eryngium ebracteatum var. poterioides: Tall and evergreen with attractive blue-green foliage and wiry stems of red-brown bobble-like flowers, Sanguisorba-like. Hardy. Up to 1.5m. [Collect Only]

Eryngium planum 'Blue Hobbit' (Sea Holly 'Blue Hobbit'): A more compact form with steely blue flowers on dark stems. Spiny glaucous foliage. Loves sunshine and very well-drained gritty soil. Hardy. Up to 30cm.

Eryngium x zabelii 'Big Blue (Sea Holly 'Big Blue): Large electric-blue thimble-shaped flowers with a spiky collar and silver-green foliage. Long flowering and bee-friendly. Hardy. Up to 75cm [Collect Only]

Eryngium x zabelii 'Jos Eijking' (Sea Holly 'Jos Eijking'): Large steely blue bracts surround a dome of tiny blue flowers in summer. Long-lasting flowers.Thrives in a sunny,dry spot. To 70cm. Hardy. [Collect Only]

Euphorbia characias subsp. wulfenii (Mediterranean spurge): Evergreen perennial with blue-green leaves and vibrant lime-green flowers in early summer. Prefers full sun. Hardy to about -10C, but not for long periods. Up to 1.2m.

Gaura lindheimeri 'The Bride': Beautiful airy stems of white flowers in mid to late summer

Gaura lindheimeri 'Whirling Butterflies': Airy stems of white flowers from pink buds, flowering in midsummer. Best in full sun, in well drained soil and a sheltered spot. Up to 1m. [Collect Only]

Geranium palmatum: Bright pink flowers held on wiry stems above rosettes of evergreen foliage. To 60cm. Frost hardy.

Gillenia trifoliata (Bowman's root): Lovely plant with starry white flowers held high over elegant foliage. Great in light shade. Hardy. [Collect Only]

Helleborus niger (Christmas Rose): Pure white flowers in midwinter, evergreen foliage.

Heuchera 'Midnight Rose': Darkest purple leaves, splashed with bright pink. Excellent for all year round foliage colour. Hardy. Up to 30cm.

Heuchera 'Obsidian' (PBR): Darkest purple leaves, almost black and glossy. Superb in pots - imagine it in a silver one!.

Kniphofia 'Nobilis' (Red hot poker 'Nobilis'): Tall, heavy spikes of orange flowers on stiff stems in late summer. A bold statement in open, dry, sunny areas [Collect Only]

Kniphofia 'Tawny King' (Red hot poker 'Tawny King'): Tall, hefty spikes of creamy orange flowers on bronze stems in mid-late summer. Superb in sunny, dry borders. [Collect Only]

Kniphofia 'Timothy' (Red hot poker 'Timothy'): Tall spikes of creamy orange flowers on bronze stems in mid-late summer. Superb in sunny, dry borders. To 1.2m. Hardy

Lamprocapnos spectabilis 'Alba' (formerly Dicentra) (Bleeding Heart, Dicentra): Pure white form of the familiar Bleeding Heart. [Collect Only]

Lamprocapnos spectabilis 'Valentine' (Bleeding Heart, Dicentra): Superb warm red flowered version of this familiar spring flowerer. Hardy. Up to 80cm. [Collect Only]

Liatris spicata 'Alba': Spikes of white flowers in mid to late summer. Very useful vertical accent. Bees adore it. To 80cm. Hardy

Lychnis chalcedonica 'Carnea' (Maltese Cross 'Carnea'): A more subtle form of the Maltese Cross with domes of pale peach pink flowers with four petals, hence its common name. Hardy. Up to 100cm.

Lychnis coronaria Atrosanguinea Group (Rose campion (dark red)): Bright magenta flowers over felty, silver foliage. Great for sunny, dry areas can be short lived in a wet, cold winter. To 1.2m Hardy.

Lychnis coronaria Gardeners' World = 'Blych' (Rose campion 'Gardeners' World'): A lovely double form of the more common single flowered plant. Stunning darkest pink flowers over silver leaves

Origanum 'Rosenkuppel' (Oregano 'Rosenkuppel'): A lovely cultivar with scented foliage and erect stems with dark pink/purple flowers. Loved by bees and butterflies. Non-edible form. Hardy. Up to 60cm.

Paeonia 'Flame' (Paeony 'Flame'): Rich and shiny scarlet red single flowers with a yellow centre. Glossy dark green leaves. Hardy. Up to 80cm. [Collect Only]

Paeonia lactiflora 'Bowl of Beauty' (Peony 'Bowl of Beauty'): Huge sugar-pink petal bowls filled with ripples of yellow ribbony bits. Swoon-worthy. [Collect Only]

Paeonia lactiflora 'Nymphe' (Peony 'Nymphe'): Strongly scented deep pink flowers with a golden centre. Attractive dark green foliage. Hardy. Up to 90cm. [Collect Only]

Paeonia officinalis 'Alba Plena' (Peony 'Alba Plena'): Sumptuous, large double white flowers above green foliage in May. A traditional cottage garden plant. May need support. [Collect Only]

Paeonia officinalis 'Rubra Plena' (Peony 'Rubra Plena'): The classic deep red double paeony. Deeply divided leaves unfurl in spring. Max Height 90cm. Flowers April to May. Full sun/partial shade. [Collect Only]

Paeonia wittmanniana: A delightful herbaceous peony with pale pink almost white bowl-shaped flowers with a yellow centre and attractive foliage. Hardy. Up to 1m. [Collect Only]

Pennisetum alopecuroides 'Hameln' (Fountain grass 'Hameln'): A deciduous clump-forming grass with spectacular feathery flowers tinged purple. Full sun. May need some protection in cold areas. Up to 1m.

Penstemon 'Garnet' (Syn. Penstemon 'Andenken an Friedrich Hahn'): Wine-red tubular flowers with white throat markings and narrow leaves. Semi-evergreen in milder areas. Protect from hard frosts.

Penstemon 'Pensham Plum Jerkum': Plum-purple tubular flowers with white throat markings. Semi-evergreen in milder areas. Protect from hard frosts. To 70cm.

Penstemon 'Schoenholzeri': Brilliant scarlet tubular flowers, slender leaves.

Primula elatior (Oxslip): Pale yellow, primrose colour flowers in clusters on gently arching stems.

Pulsatilla vulgaris 'Papageno' (Pasque flower 'Papageno'): The petals are deeply dissected, giving a frilled, double effect. Usually purple but can be pink, reddish or white. Hardy. To 30cm

Pulsatilla vulgaris Heiler hybrids: Mixed colour range, purple, pink, red or white. Lovely ornamental seed heads. Prefers a well drained, sunny site. Hardy. Up to 30cm.

Salvia x jamensis 'Nachtvlinder' (Sage 'Nachtvlinder'): Regal purple flowers on upright stems throughout late summer into autumn.

Sporobolus heterolepsis (prairie dropseed): Fine deciduous grass with green foliage in summer turning golden. Graceful flower heads in late summer. Needs sunny spot in well-drained soil. Hardy. Up to 1m.

Thalictrum 'Splendide White' (PBR) (Rue 'Splendide White'): Pure white flowers open from spherical buds. Spectacular in dappled shade [Collect Only]

Thalictrum delavayi 'Album' (Chinese meadow rue 'Album'): Dainty cup-shaped white flowers held high above fern-like greyish green leaves. To 1.2m. Hardy

Verbena bonariensis: Tall, airy but strong slender stems with flat heads of purple flowers in mid to late summer. To 1.8m. Frost-hardy.

Verbena hastata 'Alba' (American blue vervain 'Alba'): Tall, branched stems like a candelabra with spikes of small white flowers loved by bees. Needs a sheltered spot & full sun. Up to 1.2m. [Collect Only]

Verbena hastata 'Rosea' (American blue vervain 'Rosea'): Tall, branched stems like a candelabra with spikes of small pink flowers loved by bees. Needs a sheltered spot in full sun. Up to 1.2m.